Quiz 7 Communications and Networks

1. Discuss the components required for successful communications.

Computer communications describes a process in which one computer transfers data, instructions and information to another computer or computers. Successful communications require a sending device that initiates an instruction to transmit data, instructions or information, a communications device that converts or formats the data, instructions or information from the sending device into signals carried by a communications channel, and a communications channel or path on which the signals travel. Also required are a communications device that receives signals from the communications channel and converts or formats them so the receiving device can understand the signals, and a receiving device that accepts the data, instructions or information.

2. Identify various sending and receiving devices.

A sending device initiates the transmission of data, instructions, and information while a receiving device accepts the items transmitted.

Microcomputers, minicomputers, and mainframes all can serve as sending and receiving devices.

Besides, Internet appliances and Web enabled handheld computers and devices (e.g. cellular telephones and pagers) can also serve sending and receiving devices.

3. Describe uses of computer communications.

Today most computers are capable (through either a phone line or a cable connection) of exchanging information over the Internet. Your child can send a message from his or her computer to the computer of a neighbor or a friend on the other side of the planet. Students might use computers to communicate with their classmates about homework assignments, group projects, or other school-related activities. They may also use them to submit homework assignments and presentations to their teachers.

4. List advantages of using a network.

A network is a collection of computers and devices connected by communications channels that facilitates communications among users and allows users to share resources with each other. Resources may include data, information, hardware and software.

By using a network, people can communicate efficiently and easily via email, instant messaging, chat rooms, telephony, videophone calls and videoconferencing. In a networked environment, each computer on the network can access and use hardware on the network, such as printers or scanners. Authorised computers on a network can also access data and information stored on other computers in the network. Users connected to a network can access software (programs) on the network.

5. Differentiate among client/server, peer-to-peer, and P2P networks.

Network architecture is the logical design of the components of a network, including the number and type of servers, workstations and network resources. It includes the communications devices and the type of physical transmission media used to connect components.

A peer-to-peer LAN is a simple, inexpensive network that typically connects less than 10 computers together. Each computer on a peer-to-peer network can share hardware (such as a printer), data or information located on any other computer in the network. Each computer stores files on its own storage devices, and contains both the network operating system and application software. Peer-to-peer networks are ideal for very small businesses and home users. Another use of peer-to-peer, called P2P, describes an Internet network that enables users with the same networking software to connect to each other's hard disks and exchange files directly.

A client/server LAN is a network in which one or more computers acts as a server and the other computers on the network can request services from the server. A server, sometimes called the host computer, controls access to the hardware and software on the network and provides a centralised storage area for programs, data and information. The other computers on the network, called clients, rely on the server for these resources. The major difference between the server computer and the client computer is that the server has more storage space and power. Dedicated servers perform a specific task - a file server stores and manages files, a print server manages printers and print jobs, a database server stores and provides access to a database and a network server manages network traffic. A client/server network provides an efficient means to connect 10 or more computers together, but can be used to connect a smaller number of computers. A network administrator is the operations person in charge of the network.

6. Describe the various network communications standards.

Network standards defines:

•  Way devices access the medium
•  Speed on different types of networks
•  Types of network technology (cable / wireless)

Protocols

•  Rules on how devices communicate with each other
•  Data format used
•  Coding Scheme
•  Error Handling
•  Sequencing techniques etc.
•  Hardware / Software Vendors try to meet these guidelines

ANSI, IEEE

Standardizing Organization

7. Explain the purpose of communications software.

The purpose of communication software is used to provide remote access to systems and is also    used to exchange messages in text, audio and video format for the purpose of communication. This software sends and receives data over telephone lines through modems. The communication software allows computers in different geographical regions to communicate with each other through terminal emulators, file transfer programs, chat and instant messaging programs.

8. Describe various types of lines for communications over the telephone network.

A telephone network is a telecommunications network used for telephone calls between two or more parties.

There are a number of different types of telephone network:

• A fixed line network where the telephones must be directly wired into a single telephone exchange. This is known as the public switched telephone network or PSTN.
• A wireless network where the telephones are mobile and can move around anywhere within the coverage area.
• A private network where a closed group of telephones are connected primarily to each other and use a gateway to reach the outside world. This is usually used inside companies and call centres and is called a private branch exchange (PBX).

9. Describe commonly used communications devices.

Dial-up modem

• A dial-up modem converts digital signals to analog signals and vice versa
• Usually in the form of an adapter card

DSL Modem / ISDN Modem-Cable Modem

• Send and receive digital data from DSL(Digital Subscriber Line) / ISDN

Cable Modem

•  Sends and receives data over cable television (CATV) network
•  Much faster than dial-up modem or ISDN
•  Sometimes called a broadband modem

Wireless Modem 

• Allows access to the Web wirelessly from a notebook computer, a smart phone, or other mobile device. 

Hub or Switch 

• Device that provides central point for cables in network. 

Router

• Connects computers and transmits data to correct destination on network. 

10. Discuss different ways to set up a home network.

Setting up a home network

Before you start: To decide what type of network to set up or to find out what hardware and cables you need, see What you need to set up a home network. That topic has information about the different types of networks (also known as network technologies), as well as hardware requirements for each type.

Once you know what type of network you want and have the necessary hardware, there are four possible steps to take (two of these are not always required):

1.       Install any necessary hardware.

2.       Set up an Internet connection (optional).

3.       Connect the computers.

4.       Run the Set Up a Wireless Router or Access Point wizard (wireless only).

Each of these steps is described in detail later in this article.

Start by setting up one computer. Once you set up the network and you are sure that the first computer is working correctly, you can add additional computers or devices.

Install the hardware

Install network adapters in any computers that need them. (Follow the installation instructions in the information that came with each adapter.)

Set up or verify an Internet connection (optional)

You don't need an Internet connection to set up a network, although most people want to use their network to share an Internet connection. To set up an Internet connection, you need a cable or DSL modem and an account with an Internet service provider (ISP). Then open the Connect to the Internet wizard and follow the instructions.

If you already have an Internet connection, you just need to verify that the connection is working. To do that, open your web browser and go to a website that you don't usually visit. (If you go to a website that you visit often, some of its webpages might be stored on your computer and will display correctly even if your connection is faulty.) If the website opens and you don't get any error messages, your connection is working.

Connect the computers

There are several ways to connect computers—the configuration depends on the type of network adapters, modem, and Internet connection that you have. It also depends on whether or not you want to share an Internet connection among all the computers on the network. The following sections briefly describe some connection methods.

Turn on all computers or devices, such as printers, that you want to be part of your network. If your network is wired Ethernet or HPNA, it should be set up and ready to use. You should test your network (see below) to make sure that all computers and devices are connected correctly.

Run the Set Up a Wireless Router or Access Point wizard

If your network is wireless, run the Set up a Wireless Router or Access Point wizard on the computer attached to the router.

·         Open Set Up a Wireless Router or Access Point by clicking the Start button, clicking Control Panel, clicking Network and Internet, and then clicking Network and Sharing Center. In the left pane, click Set up a connection or network, and then click Set up a wireless router or access point.

The wizard will walk you through the process of adding other computers and devices to the network. For more information, see Add a device or computer to a network.

Test your network

It's a good idea to test your network to make sure that all of the computers and devices are connected and working properly. To test your network, do the following on each network computer: Click the Start button, and then click Network. You should be able to see icons for the computer you are on and all of the other computers and devices that you have added to the network. If the computer you are checking has a printer attached, the printer icon might not be visible on other computers until you enable printer sharing. (Printer sharing is not available on Windows Vista Starter.)

Changing TCP/IP settings

If you need to adjust TCP/IP settings for your network, see Change TCP/IP settings.

Connecting your mobile PC from work to your home network

To connect the mobile PC that you use at work to the Internet or to your work network from your home network, you must have a network connection set up at home. For information about using your mobile PC on your home network, see Switching between your home and workplace networks.

11. Identify various physical and wireless transmission media.

Quiz 6 - Operating Systems and Utility Programs

1.Define system software and identify the two types of system software.

System software

  Two Types of Software System

 An operating system (OS) is a set of programs containing instructions that work together to coordinate all the activities among computer hardware resources.

A utility program is a type of system software that allows a user to perform maintenance-type tasks

 2.Briefly describe various server operating systems: Windows Server, UNIX,Linux, Solaris, and NetWare.

UNIX
Linux is an open-source, popular, multitasking UNIX-type operating system
 3.Summarize the features of several embedded operating systems: Windows Embedded CE, Windows Mobile, Palm OS, iPhone OS, BlackBerry, Google Android, Embedded Linux, and Symbian OS.

4.Explain the purpose of several utility programs: file manager, search utility, image viewer, uninstaller, disk cleanup, disk defragmenter, backup and
restore utilities, screen saver, personal firewall, antivirus programs, spyware and adware removers, Internet filters, file compression, media player, disc burning, and personal computer maintenance.

A file manager is a utility that performs functions related to file management
–
–
–Copying, renaming, deleting, moving, and sorting files and folders –
A search utility is a program that attempts to locate a file on your computer based on criteria you specify
•A disk cleanup utility searches for and removes unnecessary files –Downloaded program files –Temporary Internet files –Deleted files –Unused program files
•An uninstaller removes a program, as well as any associated entries in the system files An image viewer allows users to display, copy, and print the contents of a graphics file Creating shortcuts Organizing files in folders Displaying a list of files is a multitasking operating system developed in the early 1970s consists of the programs that control or maintain the operations of the computer and its devices

quiz 5

1. Differentiate between storage devices and storage media.
 answer:
Storage device refers to the apparatus for recording computer data. Examples are the RAM, floppy drives, ZIP drives, and other disks drives. While, storage media are the materials on which data are written and stored. Examples are the floppy disks, optical discs, hard disks, etc.
2. Identify the uses of tape, magnetic stripe cards, smart cards, microfilm and microfiche, and enterprise storage.

Tape is a magnetically coated ribbon of plastic capable of storing large amounts of data and information at a low cost. A tape drive reads and writes data and information on tape. Business users utilize tape most often for long-term storage and backup. A magnetic stripe card is a credit card, entertainment card, bank card, or other similar card with a stripe that contains information identifying you and the card. A magnetic stripe card reader reads the information stored on the stripe. A smart card, which is similar in size to a credit or ATM card, stores data on a thin microprocessor embedded in the card. A smart card reader reads the information on the smart card and updates it if necessary. Microfilm is a 100- to 215-foot roll of film. Microfiche is a small sheet of film, usually about 4 X 6 inches. Microfilm and microfiche reduce the amount of paper firms must handle, are inexpensive, and have the longest life of any storage media. Enterprises use computers, servers, and networks to manage and store huge volumes of data and information. In an enterprise, some storage systems can provide more than 185 TB of storage, and optical disc servers hold hundreds of optical discs.

3. Describe the various types of flash memory storage: solid state drives, memory cards, USB flash drives, and ExpressCard modules.

Flash memory chips are a type of solid state media, which means they consist entirely of electronic components and contain no moving parts. A solid state drive (SSD) typically uses flash memory to store data, instructions, and information. A memory card is a removable flash memory device that you insert and remove from a slot in a computer, mobile device, or card reader/writer. Common memory cards include CompactFlash (CF), Secure Digital (SD), Secure Digital High Capacity (SDHC), microSD, microSDHC, xD Picture Card, Memory Stick, and Memory Stick Micro (M2). A USB flash drive, sometimes called a thumb drive, is a flash memory storage device that plugs in a port on a computer or mobile device. An ExpressCard module is a removable device that fits in an ExpressCard slot. Express Card modules can add memory, storage, communications, or other capabilities to a computer.

4. Differentiate among various types of optical discs: CDs, archive discs and Picture CDs, DVDs, and Blu-ray Discs.

A CD-ROM, or compact disc read-only memory, is a type of optical disc that uses laser technology to store items. Users can read the contents of standard CD-ROMs but cannot erase or modify their contents. A CD-R (compact disc-recordable) is a multisession disc on which users can record their own items, such as text, graphics, and audio. Each part of a CD-R can be written on only one time, and the disc's contents cannot be erased. A CD-RW (compact disc-rewritable) is an erasable disc that can be written on multiple times. An archive disc stores photos from an online photo center in the jpg file format. A Picture CD is a single-session CD-ROM that stores digital versions of film using the jpg format at a lower resolution than an archive disc. A DVD-ROM (digital versatile disc-read-only memory or digital video disc-read-only memory) is a high capacity optical disc that you can read but not write on or erase. A newer, more expensive DVD format is Blu-ray Disc-ROM (BD-ROM), with higher capacity and better quality than standard DVDs. Many types of recordable and rewritable DVD formats are available. DVD-R and DVD+R are DVD-recordable formats. BD-R is a high-capacity DVD-recordable format. DVD-RW, DVD+RW, and DVD+RAM are rewritable DVD formats that allow users to erase and record multiple times. BD-RE is a high-capacity rewritable DVD format.

5. Summarize the characteristics of ink-jet printers, photo printers, laser printers, multifunction peripherals, thermal printers, mobile printers, label and postage printers, and plotters and large-format printers

An inkjet printer is a type of computer printer that creates a digital image by propelling droplets of ink onto paper. Inkjet printers are the most commonly used type of printer.
Laser printers operate by shining a laser beam to produce an image on a drum. The drum is then rolled through a pool, or reservoir, or toner, and the electrically charged portions of the drum pick up ink. Finally, using a combination of heat and pressure, the ink on the drum is transferred onto the page. Laser printers print  very fast, and the supply cartridges work a long time. Color laser printers use the same toner-based printing process as black and white ( B/W) laser printers, except that they combine four different toner colors.  Color laser printers can also be used as a regular black and white laser printer. 

Multifunction printers: combine top-quality color ink-jet or laser printing with plain-paper and PC faxing, color copying and color scanning , telephoning- all in one convenient, space-saving machine. If you work from home or have a small office a multifunctional device may be ideal. 
Label Printers are  the smartest way to print labels one at a time.  The printers allow easy installation.  You can  get high-quality, professional results every time. There are multi-purpose  printers , that can print different types of labels. For example, label printers used in supermarkets can print bar codes as well as normal text. There are also some label printers that can print different sizes of labels on goods.
Plotters  (Designjet) are large-scale printers that are very accurate at reproducing line drawings. They are commonly used for technical drawings such as engineering drawings or architectural blueprints. The two basic types of plotters are called flatbed plotters and drum plotters. Flatbed plotters are horizontally aligned with a flat surface to which a piece of paper is attached. The paper remains stationary and the printer moves pens across the paper to draw the image. Drum plotters, also called upright plotters, are vertically positioned. They have a drum that the paper rolls on. Drum plotters usually make more noise and are more compact than flatbed plotters. 
Portable printers are usually fairly lightweight and sometimes carry the option of using a battery instead of drawing power from the computer. Usually they realize basic print resolutions suitable for plain text printing. You can find on the market the following types of the portable printers:  Thermal printer, Thermal transfer printer and Ink-Jet printer. The main advantage of thermal and thermal transfer printers is that they can be very small. The smallest thermal and  thermal transfer printers  weigh  approximately one pound. Usually the  ink-jet portable printer weighs more than 2 pounds. Thermal printers require a special type of paper.

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kadaghan sa buhaton hahay...................

quiz 3

quiz 3

1. Describe the four categories of output.
 Text consists of characters (letters, numbers, punctuation marks, or any other symbol requiring one byte of computer storage space) that are used to create words, sentences, and paragraphs. Graphics are digital representations of non text information such as drawings, charts, photographs, and animation (a series of still images in rapid sequence that gives the illusion of motion). Audio is music, speech, or any other sound. Video consists of images played back at speeds to provide the appearance of full motion

2. The characteristics of LCD monitor LCD screens, plasma monitors, and HDTVs.

A liquid crystal display (LCD) is a thin, flat electronic visual display that uses the light modulating properties of liquid crystals (LCs). LCs do not emit light directly.

They are used in a wide range of applications, including computer monitors, television, instrument panels, aircraft cockpit displays, signage, etc. They are common in consumer devices such as video players, gaming devices, clocks, watches, calculators, and telephones. LCDs have displaced cathode ray tube (CRT) displays in most applications. They are usually more compact, lightweight, portable, less expensive, more reliable, and easier on the eyes.^{[citation needed]} They are available in a wider range of screen sizes than CRT and plasma displays, and since they do not use phosphors, they cannot suffer image burn-in.

Plasma displays are bright (1,000 lux or higher for the module), have a wide color gamut, and can be produced in fairly large sizes—up to 150 inches (3.8 m) diagonally. They have a very low-luminance "dark-room" black level compared to the lighter grey of the unilluminated parts of an LCD screen (i.e. the blacks are blacker on plasmas and greyer on LCDs). LED-backlit LCD televisions have been developed to reduce this distinction. The display panel itself is about 6 cm (2.5 inches) thick, generally allowing the device's total thickness (including electronics) to be less than 10 cm (4 inches). Plasma displays use as much power per square meter as a CRT or an AMLCD television. Power consumption varies greatly with picture content, with bright scenes drawing significantly more power than darker ones – this is also true of CRTs. Typical power consumption is 400 watts for a 50-inch (127 cm) screen. 200 to 310 watts for a 50-inch (127 cm) display when set to cinema mode. Most screens are set to 'shop' mode by default, which draws at least twice the power (around 500–700 watts) of a 'home' setting of less extreme brightness. Panasonic has greatly reduced power consumption ("1/3 of 2007 models"). Panasonic states that PDPs will consume only half the power of their previous series of plasma sets to achieve the same overall brightness for a given display size. The lifetime of the latest generation of plasma displays is estimated at 100,000 hours of actual display time, or 27 years at 10 hours per day. This is the estimated time over which maximum picture brightness degrades to half the original value.

Plasma display screens are made from glass, which reflects more light than the material used to make an LCD screen. This causes glare from reflected objects in the viewing area. Companies such as Panasonic coat their newer plasma screens with an anti-glare filter material. Currently, plasma panels cannot be economically manufactured in screen sizes smaller than 32 inches. Although a few companies have been able to make plasma EDTVs this small, even fewer have made 32in plasma HDTVs. With the trend toward larger and larger displays, the 32in screen size is rapidly disappearing. Though considered bulky and thick compared to their LCD counterparts, some sets such as Panasonic's Z1 and Samsung's B860 series are as slim as one inch thick making them comparable to LCDs in this respect.

High-definition television (or HDTV) is video that has resolution substantially higher than that of traditional television systems (standard-definition TV, or SDTV, or SD). HDTV has one or two million pixels per frame, roughly five times that of SD. Early HDTV broadcasting used analog techniques, but today HDTV is digitally broadcast using video compression.

3. What are the components inside the systems units?

The system unit, sometimes called the chassis, is a box-like case housing the electronic components of a computer that are used to process data. System unit components include the processor, memory module, cards, ports, and connectors. Many of the system unit’s components reside on a circuit board called the motherboard. The motherboard contains many different types of chips, or small pieces of semi conducting material, on which one or more integrated circuits (IC) are etched. An integrated circuit is a microscopic pathway capable of carrying electronic current. Each IC can contain millions of transistors, which act as switches for electronic signals.

4. The components of a processor and how they complete a machine cycle.

·         Control unit is responsible for supervising the operation of the entire computer system.

·         Arithmetic/logic unit (ALU) provides the computer with logical and computational capabilities.

·         Register is a storage location inside the processor.

5. Define a bit and describe how a series of bits represents data.

A bit (a contraction of binary digit) is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states.

When the user presses any letter using the keyboard the electronic signal from that letter is sent to the system unit. Then the system unit converts it to its binary code and stored in memory for processing. After processing the binary code for that particular letter is converted to an image and displayed on the output device (monitor).

6. Identify the categories of application software.

Word Processing Software allows users to create, edit a document. Example: MS Word, Word Pad etc.

Spreadsheet Software allows users to create document and perform calculation. Example: Excel, Lotus1-2-3 etc.

Database Software allows users to store and retrieve vast amount of data. Example: MS Access, MySQL, Oracle etc.

Presentation Graphic Software allows users to create visual presentation. Example: MS Power Point

Multimedia Software allows users to create image, audio, video etc. Example: Real Player, Media Player etc.

7. Identify the key features of widely used business programs.

People use productivity software to become more effective and efficient while performing daily activities. Word processing software allows users to create and manipulate documents that contain text and graphics. With word processing software, you can insert clip art into a document; change margins; find and replace text; use a spelling checker to check spelling; place a header and footer at the top and the bottom of a page; and vary font (character design), font size (character scale), and font style (character appearance).

With spreadsheet software, data is organized in rows and columns, which collectively are called a worksheet. The intersection of a row and column, called a cell, can contain a label (text), a value (number), or a formula or function that performs calculations on the data and displays the result.

Database software allows you to create and manage a database. A database is a collection of data organized to allow access, retrieval, and use of that data. A query is used to retrieve data according to specified criteria, which are restrictions the data must meet.

Presentation graphics software is used to create presentations that communicate ideas, messages, and other information to a group through a slide show. You can use a clip gallery to enhance your presentation with clip art images, pictures, video clips, and audio clips.

A personal information manager (PIM) is software that includes an appointment calendar to schedule activities, an address book to maintain names and addresses, and a notepad to record ideas, reminders, and important information. A software suite is a collection of individual applications sold as a single package.

Project management software allows you to plan, schedule, track, and analyze the progress of a project. Accounting software helps companies record and report their financial transactions.

Power users often use software that allows them to work with graphics and multimedia. Computer-aided design (CAD) software assists in creating engineering, architectural, and scientific designs. Desktop publishing (DTP) software is used to design and produce sophisticated documents. DTP is developed specifically to support page layout, which is the process of arranging text and graphics in a document. Paint software is used to draw graphical images with various on-screen tools. Image editing software provides the capability to modify existing images. Video editing software and audio editing software can be used to modify video and audio segments.

Multimedia authoring software is used to create electronic interactive presentations that can include text, images, video, audio, and animation. Web page authoring software is designed to create Web pages and to organize, manage, and maintain Web sites.

Many software applications are designed specifically for use at home or for personal or educational use. Integrated software combines several productivity software applications that share a similar interface and common features into a single package. Personal finance software is an accounting program that helps pay bills, balance a checkbook, track income and expenses, follow investments, and evaluate financial plans. Legal software assists in the creation of legal documents and provides legal advice. Tax preparation software guides users through the process of filing federal taxes. Personal DTP software helps develop conventional documents by asking questions, presenting predefined layouts, and supplying standard text.

Photo-editing software is used to edit digital photographs. A clip art/image gallery is a collection of clip art and photographs that can be used in all types of documents. Home design/landscaping software assists with planning or remodeling. Educational software teaches a particular skill and exists for about any subject. Reference software provides valuable and thorough information for all individuals. Entertainment software includes interactive games, videos, and other programs designed to support a hobby or provide amusement.

One of the main reasons people use computers is to communicate and share information. E-mail software is used to create, send, receive, forward, store, print, and delete e-mail (electronic mail). A Web browser is a software application used to access and view Web pages. A chat client is software that allows you to connect to a chat room, which permits users to chat via the computer. A newsreader is a software program used to participate in a newsgroup, which is an online area on the Web where users conduct written discussion about a particular subject. An instant messenger is a software program installed to use instant messaging (IM), a real-time communications service that notifies you when one or more people are online and then allows you to exchange messages or files. Groupware is a software application that helps groups of people on a network work together and share information. A videoconference is a meeting between two or more geographically separated people who use a network or the Internet to transmit audio and video data.

8. What are the advantages of using application software on the Web?

Advantages of Web Applications

·         No special configurations of changes are need on user’s PCs.

·         Lower costs

·         Centralized data is secure and easy to backup.

·         Updates can be made quickly and easily.

·         Information is accessible to a wide audience anywhere in the world.

·         Available 24 hours a day, 7 days a week.

·         Everybody has a browser – familiar interface encourages use.

·         Online training can be completed at user’s own time and pace.

·         Always up-to-date.

9. History of the Internet.

The history of the Internet starts in the 1950s and 1960s with the development of computers. This began with point-to-point communication between mainframe computers and terminals, expanded to point-to-point connections between computers and then early research into packet switching. Packet switched networks such as ARPANET, Mark I at NPL in the UK, CYCLADES, Merit Network, Tymnet, and Telenet, were developed in the late 1960s and early 1970s using a variety of protocols. The ARPANET in particular led to the development of protocols for internetworking, where multiple separate networks could be joined together into a network of networks.

In 1982 the Internet Protocol Suite (TCP/IP) was standardized and the concept of a world-wide network of fully interconnected TCP/IP networks called the Internet was introduced. Access to the ARPANET was expanded in 1981 when the National Science Foundation (NSF) developed the Computer Science Network (CSNET) and again in 1986 when NSFNET provided access to supercomputer sites in the United States from research and education organizations. The ARPANET was decommissioned in 1990. Commercial internet service providers (ISPs) began to emerge in the late 1980s and 1990s and the Internet was commercialized in 1995 when NSFNET was decommissioned, removing the last restrictions on the use of the Internet to carry commercial traffic.

Since the mid-1990s the Internet has had a drastic impact on culture and commerce, including the rise of near instant communication by electronic mail, instant messaging, Voice over Internet Protocol (VoIP) "phone calls", two-way interactive video calls, and the World Wide Web with its discussion forums, blogs, social networking, and online shopping sites. The research and education community continues to use advanced networks such as NSF's very high speed Backbone Network Service (vBNS) and Internet2. Increasing amounts of data are transmitted at higher and higher speeds over fiber optic networks operating at 1-Gbit/s, 10-Gbit/s, or more. The Internet continues to grow, driven by ever greater amounts of online information and knowledge, commerce, entertainment and social networking.

10. What are different storage devices?

1.       Hard Drive (Internal)

Internal Hard Drive

You computer's hard drive is the first most important type of storage. Anything that you download, applications that you install, your pictures, videos and music are all stored directly to your hard drive. Basically, anything that is on your computer is stored to your internal hard drive. Internal hard drive capacity is measured in gigabytes. For example, you may have a 500GB SATA hard drive on your computer. Also, internal computer hard drives have different speeds such as 5400RPM and 7200RPM. This reading is the speed that the hard drive disk spins. A faster hard drive will have higher RPM. The faster the hard drive spins, the faster your hard drive can read data, as well as write data.

2.       External Hard Drives

External Hard Drive

External hard drives are exactly the same as internal drives, with one exception. Rather then being enclosed inside your computer, external hard drives have their own separate casing and sit externally to your computer. External hard drives can connect to your computer in a variety of ways. Some common connection types are: USB 2.0, ESATA, Firewire 400 and Firewire 800. External hard drives measure capacity in gigabytes and have different speeds as well. For the most part, external hard drives are used for backup and storing files that a computer user may want to transport.

3.       Network Attached Storage

NAS Server

Another common form of computer storage is network attached storage or NAS. Network attached storage is a method commonly used by businesses to share files between computers. A NAS is simply a storage device connected to a computer network. This is beneficial because many computers can read and write to a NAS. Network attached storage capacity is measured in gigabytes. Also, NASs are available with different hard drive speeds.

Many at home computer users often create their own NAS devices by connecting an external hard drive to their router. This allows them to access it wirelessly, as well as share it with other computers.

4.       Optical Media Storage

Optical Drive

Optical media storage is basically writing data to a CD or DVD. When your burn a CD, you are storing songs and music on the CD so that you can listen to it later. If you are burning a DVD, you are storing a video on it so that you can watch it later. CD-RW and DVD-RW media has the capability to be recorded on and erased later if necessary. This makes optical media storage ideal for transporting relatively small amounts of data.

5.       Flash Drives

Flash Drive

Flash drives, or thumb drives, are one of the newest forms of computer storage. These drives connect to any computer by way of USB. Often times, students as well as business professionals, use flash drives as a simple way to transport text documents to and from work, and to and from school. When flash drives were first released, storage capacity was rather limited. However, companies are now manufacturing flash drives with huge storage capacities, up to 64GB.

quiz 2

1. Describe various types of pen input, and identify other types of input for smart phones.

Light Pen - Light pen is actually one more pointing input gadget. This will pick up on existence of light. It's a hand held pen fashioned gadget having a photocell installed in it's front-end. Once the front-end on the pen is actually touched on the display screen, the actual photocell registers a position associated with display. This kind of instrument also offers a button. An individual points to the actual object that will end up being chosen on the display screen using the light pen after which clicks the button in the pen. Light pen gadgets are utilized by technical engineers, visual creative designers and so on. These types of gadgets call for unique displays. Light pen can be used on PDA's and also other kinds of portable computers.
The electrical light pen input instrument is usually combined with creating computer software. Designed screen data files are usually joined using a light pen simply by directing it to display positions. A new place shows up on the screen in the area exactly where pen is placed which is sensed through the photocell. The pc software operated the feedback transmission of the instrument.
Digitizer - A Digitizer is also called a graphic tablet and uses a pen input device. It's a flat, rectangle-shaped digital plastic material pad. Every position to the digitizer points to matching video display. It's primarily useful for producing road maps and also engineering blueprints. The actual input gadgets stylus pen and also cursor can be used to trace sketches and also drawings to the digitizer.
Whenever you sketch upon the digitizer with the aid of the stylus pen or cursor, this converts the actual actions associated with stylus or cursor straight into electronic signals which are afterwards routed to the laptop or computer. Therefore a digitizer makes it simple to key in free-hand sketching in to a laptop or computer.
Stylus and Cursor - Stylus pen is actually like a ballpoint pen. It's utilized to compose textual content or make lines (or generate drawings and also pictures) on the exclusively developed graphics display or digitizer. Pen input devices found in several sophisticated graphic devices is called Digital Pen. Generally electronic digital pen supplies much more performance compared to stylus pen.
Stylus pen can be used in graphic programs for instance Computer Aided Design (CAD) and also engineering blueprints and so forth. It's got the convenience of removing textual content as well as lines.
Several portable personal computers make use of touch screens which permit someone to enter any data and even to enable selections in the monitor utilizing a stylus pen or a digital pen. PDA's utilize pen input devices along with tablet Computers quite often use a digital pen. These laptop or computer operates one-of-a-kind platforms also known as optical character recognition. Such a program converts written characters along with symbols to a mode which the computer systems may use and also process all of them.
The actual cursor is surely an input product. It's also used to trace sketches and also drawings with a graphic tablet or perhaps digitizer. This appears like some sort of computer mouse, with the exception of it's got a window using crosshairs, therefore the end user is able to see through to the actual digitizer. Cursor is generally known as Puck.



2. The purpose of various game controllers: gamepads, joysticksand wheels, light guns, dance pads,
and motion-sensing game controllers.

A gamepad, also known as a joypad, is the most common kind of game controller. They are held in both hands with thumbs and fingers used to provide input. Gamepads can have a number of action buttons combined with one or more omnidirectional control sticks or buttons. Action buttons are generally handled with the digits on the right hand, and the directional input handled with the left. Gamepads are the primary means of input on nearly all modern video game consoles. Due to the ease of use and precision of gamepads, they have spread from their origin on traditional consoles to computers, where a variety of games and emulators support their input.
Most modern game controllers are a variation of a standard gamepad. Common additions include shoulder buttons placed along the edges of the pad, centrally placed buttons labeled start, select, and mode, and an internal motor to provide haptic feedback.

This joystick is a peripheral that consists of a handheld stick that can be tilted around either of two axes and (sometimes) twisted around a third. The joystick is often used for flight simulators. HOTAS controllers, composed of a joystick and throttle quadrant (see below) are a popular combination for flight simulation among its most fanatic devotees. Most joysticks are designed to be operated with the user's primary hand (e.g. with the right hand of a right-handed person), with the base either held in the opposite hand or mounted on a desk.

The steering wheel, essentially a larger version of a paddle, is used in most racing arcade games as well as more recent racing simulators such as Live for Speed, Grand Prix Legends, GTR2, and Richard Burns Rally. While most arcade racing games have been using steering wheels since Speed Race in 1974,^[1] the first steering wheels for home systems appeared on fifth-generation consoles such as the PlayStation and Nintendo 64.^{[citation needed]}
Many are force feedback (see Force Feedback Wheel), designed to give the same feedback as would be experienced when driving a real car, but the realism of this depends on the game. They usually come with pedals to control the gas and brake. Shifting is taken care of with in various different ways including paddle shifting systems, simple stick shifters which are moved forward or back to change gears or more complex shifters which mimic those of real vehicles, which may also use a clutch. Most wheels turn only 200 to 270 degrees lock-to-lock but some models, such as the Logitech Driving Force Pro, Logitech G25 and Logitech G27 can turn 900 degrees, or 2.5 turns, lock-to-lock.
The Namco Jogcon paddle was available for the PlayStation game R4: Ridge Racer Type 4. Unlike "real" video game steering wheels, the Jogcon was designed to fit in the player's hand. Its much smaller wheel (diameter roughly similar to a soda can's) resembles the jog-and-shuttle control wheel used on some VCRs.

A light gun is a peripheral used to "shoot" targets on a screen. They usually roughly resemble firearms or ray guns. Their use is normally limited to rail shooters, or shooting gallery games like those that came with the Shooting Gallery light gun. A rare example is Taito's 1992 arcade game Gun Buster, a first-person shooter that used a joystick to move and a light gun to aim.^[6]
Though light guns have been used in earlier arcade games such as Sega's Periscope in 1966^[7] and Missile in 1969,^[8] the first home console light gun was released for the Magnavox Odyssey in 1972; later on, Nintendo would include one standard on their Famicom and NES, called the NES Zapper. Nintendo has also released a "shell" in the style of a light gun for the more recent Wii Remote called the Wii Zapper which comes bundled with Link's Crossbow Training.

A dance pad, also known as a dance mat, dance platform, or jitter deck is a flat electronic game controller used for input in dance games. Most dance pads are divided into a 3×3 matrix of square panels for the player to stand on, with some or all of the panels corresponding to directions or actions within the game. Some dance pads also have extra buttons outside of the main stepping area, such as "Start" and "Select". Pairs of dance pads are often joined side-by-side for certain gameplay modes.



3. Explain how resolution affects the quality of a picture captured on a
digital camera.

Image resolution describes the detail an image holds. The term applies to raster digital images, film images, and other types of images. Higher resolution means more image detail.
Image resolution can be measured in various ways. Basically, resolution quantifies how close lines can be to each other and still be visibly resolved. Resolution units can be tied to physical sizes (e.g. lines per mm, lines per inch), to the overall size of a picture (lines per picture height, also known simply as lines, or TV lines), or to angular subtenant. Line pairs are often used instead of lines; a line pair comprises a dark line and an adjacent light line. A Line (or TV line, TVL) is either a dark line or a light line. A resolution of 10 lines per millimeter means 5 dark lines alternating with 5 light lines, or 5 line pairs per millimeter (5 LP/mm). Photographic lens and film resolution are most often quoted in line pairs per millimeter.


4. Describe the uses of voice recognition, Web cams, and video conferencing.

Voice recognition is the process of taking the spoken word as an input to a computer program. This process is important to virtual reality because it provides a fairly natural and intuitive way of controlling the simulation while allowing the user's hands to remain free.

A webcam is a video camera which feeds its images in real time to a computer or computer network, often via USB, ethernet or Wi-Fi

Videocalling and conferencing

As webcam capabilities have been added to instant messaging, text chat services such as AOL Instant Messenger, and VoIP services such as Skype, one-to-one live video communication over the Internet has now reached millions of mainstream PC users worldwide. Improved video quality has helped webcams encroach on traditional video conferencing systems. New features such as automatic lighting controls, real-time enhancements (retouching, wrinkle smoothing and vertical stretch), automatic face tracking and autofocus assist users by providing substantial ease-of-use, further increasing the popularity of webcams.
Webcam features and performance can vary by program, computer operating system, and also by the computer's processor capabilities. For example, 'high-quality video' is principally available to users of certain Logitech webcams if their computers have dual-core processors meeting certain specifications. Video calling support has also been added to several popular instant messaging programs.

 Video security

Webcams are also used as security cameras. Software is available to allow PC-connected cameras to watch for movement and sound, recording both when they are detected; these recordings can then be saved to the computer, e-mailed or uploaded to the Internet. In one well-publicised case,^[9] a computer e-mailed out images as the burglar stole it, allowing the owner to give police a clear picture of the burglar's face even after the computer had been stolen.

 Video clips and stills

Webcams can be used to take Video clips and still pictures. Various software tools in wide use can be employed for this, such as PicMaster (for use with Windows operating systems), Photo Booth (Mac), or Cheese (with Unix systems). Input control devices

Special software can use the video stream from a webcam to assist or enhance a user's control of applications and games. Video features, including faces, shapes, models and colors can be observed and tracked to produce a corresponding form of control. For example, the position of a single light source can be tracked and used to emulate a mouse pointer, a head mounted light would allow hands-free computing and would greatly improve computer accessibility. This can also be applied to games, providing additional control, improved interactivity and immersiveness.FreeTrack is a free webcam motion tracking application for Microsoft Windows that can track a special head mounted model in up to six degrees of freedom and output data to mouse, keyboard, joystick and FreeTrack supported games By removing the IR filter of the webcam, IR LEDs can be used, which has the advantage of being invisible to the naked eye, removing a distraction from the user. TrackIR is a commercial version of this technology.
The EyeToy for the PlayStation 2 (The updated PlayStation 3 equivalent is the PlayStation Eye) and similarly the Xbox Live Vision Camera and the Kinect AKA 'Project Natal' for the Xbox 360 and Xbox Live are color digital cameras that have been used as control input devices by some games.
Small webcam-based PC games are available as either standalone executables or inside web browser windows using Adobe Flash.

A videoconference or video conference (also known as a videoteleconference) is a set of interactive telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously. It has also been called 'visual collaboration' and is a type of groupware



5. Discuss how various scanners and reading devices work: optical scanners,
optical readers, bar code readers, RFID readers, magnetic stripe card
readers, MICR readers, and data collection devices.
6. Summarize the various biometric devices: fingerprint reader, face
recognition system, hand geometry system, voice verification system,
signature verification system, and iris recognition system