Quiz No. 7

Answers:

1. Sending device — initiates instruction to transmit data, instructions, or information

Communications device — connects the sending device to the communications channel
Communications channel — media on which data, instructions, or information travel
Communications device — connects the communications channel to the receiving device
 Receiving device — accepts transmission of data, instructions, or information

2.

Text messaging allows users to send and receive short text messages

Picture messaging allows users to send graphics, pictures, video clips, sound files, and short text messages

3. 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.

A user can logon to a computer anywhere on the network and access their work files from the file server.

Computers can be managed centrally - with the same software installed on each one.

Time - it is much faster to install an application once on a network - and copy it across the network to every workstation.

Sharing printers, plotters, modems etc saves money and time.

Security - the Network Manager can allocate usernames and passwords to all users to try to prevent unauthorized access.

It is easy and convenient to monitor users - for example websites visited or documents printed - this can be done using software running on the server.

5. A server a computer program running to serve the needs or requests of other programs (referred to in this context as "clients") which may or may not be running on the same computer. Peer-to-peer (P2P) computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the application.
6. A network standard defines guidelines that specify the way computers access the medium to which they are attached the speeds used on different types of networks, and the types of physical cable and/or wireless technology used. 
Ethernet: network standard that specifies no central computer or device on the network (nodes) should control when data can be transmitted; that is, each node attempts to transmit data when it determines the network is available to receive communications. Also based on a bus topology but can be wired in a star pattern.

 7. Office Intercom lets you use your computer to speak to others over the     

internet or your local office computer network. It works as a virtual

intercom and feels a little like using a CB radio. To talk to anyone else who

has installed Office Intercom anywhere in the world, just hold down a key

on the keyboard. Speak into your computer's microphone and you will be

heard through the other computer's speakers. You can assign system-wide

'hot' keys, or use hardwired buttons or a Speech Mike handset to connect

directly without opening Office Intercom.

Quiz No. 7

Questions:
1. Discuss the components required for successful communications.

2. Identify various sending and receiving devices.

3. Describe uses of computer communications.

4. List advantages of using a network.

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

6. Describe the various network communications standards.

7. Explain the purpose of communications software.

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

9. Describe commonly used communications devices.

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

11. Identify various physical and wireless transmission media.

Quiz No. 6

Answers:

1. 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. UNIX
Linux is an open-source, popular, multitasking UNIX-type operating system
3. 
4. 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 No. 6

Questions:
1.Define system software and identify the two types of system software.
2.Briefly describe various server operating systems: Windows Server, UNIX,Linux, Solaris, and NetWare.
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.

Quiz No. 5

Answers:
1. A storage device is a hardware device capable of storing information. There are two storage devices used in computers; a primary storage device such as computer RAM and a secondary storage device such as a computer hard disk drive. In the picture to the right, is an example of a Drobo, an external secondary storage device. In computers, a storage medium is any technology (including devices and materials) used to place, keep, and retrieve data. A medium is an element used in communicating a message; on a storage medium, the "messages" - in the form of data - are suspended for use when needed. The plural form of this term is storage media. Although the term storage includes both primary storage (memory), a storage medium usually means a place to hold secondary storage such as that on a hard disk or tape.
2. A tape drive is a data storage device that reads and writes data on a magnetic tape. It is typically used for offline, archival data storage. Tape media generally has a favorable unit cost and long archival stability.
A tape drive provides sequential access storage, unlike a disk drive, which provides random access storage. A disk drive can move its read/write head(s) to any random part of the disk in a very short amount of time, but a tape drive must spend a considerable amount of time winding tape between reels to read any one particular piece of data. As a result, tape drives have very slow average seek times. Despite the slow seek time, tape drives can stream data to and from tape very quickly. For example, popular Linear Tape-Open drives can reach, as of 2010, continuous data transfer rates of up to 140 MB/s, which is comparable to hard disk drives.
3. A solid-state drive (SSD) is a data storage device that uses solid-state memory to store persistent data with the intention of providing access in the same manner of a traditional block i/o hard disk drive. SSDs are distinguished from traditional hard disk drives (HDDs), which are electromechanical devices containing spinning disks and movable read/write heads.A memory card or flash card is an electronic flash memory data storage device used for storing digital information. They are commonly used in many electronic devices, including digital cameras, mobile phones, laptop computers, MP3 players, and video game consoles. They are small, re-recordable, and able to retain data without power.A USB flash drive consists of a flash memory data storage device integrated with a USB (Universal Serial Bus) interface. USB flash drives are typically removable and rewritable, and physically much smaller than a floppy dis ExpressCard is an interface to allow peripheral devices to be connected to a computer, usually a laptop computer. Formerly called NEWCARD, the ExpressCard standard specifies the design of slots built into the computer and of cards which can be inserted into ExpressCard slots. The cards contain electronic circuitry and connectors to which external devices can be connected. The ExpressCard standard replaces the PC Card (also known as PCMCIA) standards.
4. The Compact Disc (also known as a CD) is an optical disc used to store digital data. It was originally developed to store and playback sound recordings exclusively, but later expanded to encompass data storage (CD-ROM), write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Discs (VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD. Audio CDs and audio CD players have been commercially available since October 1982.Picture CD is a product by Kodak, following on from the earlier Photo CD product. It holds photos from a single roll of color film, stored at 1024×1536 resolution using JPEG compression. The product is aimed at consumers. Software to view and perform simple edits to images is included on the CD.DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than compact discs while having the same dimensions.Blu-ray Disc (official abbreviation BD) is an optical disc storage medium designed to supersede the DVD format. The disc diameter is 120 mm and disc thickness 1.2 mm plastic optical disc, the same size as DVDs and CDs. Blu-ray Discs contain 25 GB (23.31 GiB) per layer, with dual layer discs (50 GB), the norm for feature-length video discs. Triple layer discs (100 GB) and quadruple layers (128 GB) are available for BD-XL Blu-ray re-writer drives. Currently movie production companies have not utilized the triple or quadruple layer discs, most consumers owned Blu-ray players will not be able to read the additional layers, while newer Blu-ray players may require a firmware update to play the triple and quadruple sized discs.
5. 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 and range from small inexpensive consumer models to very large professional machines that can cost up to thousands of dollars.A laser printer is a common type of computer printer that rapidly produces high quality text and graphics on plain paper. As with digital photocopiers and multifunction printers (MFPs), laser printers employ a xerographic printing process, but differ from analog photocopiers in that the image is produced by the direct scanning of a laser beam across the printer's photoreceptor.An MFP (Multi Function Product/ Printer/ Peripheral), multifunctional, all-in-one (AIO), or Multifunction Device (MFD), is an office machine which incorporates the functionality of multiple devices in one, so as to have a smaller footprint in a home or small business setting (the SOHO market segment), or to provide centralized document management/distribution/production in a large-office setting.A thermal printer (or direct thermal printer) produces a printed image by selectively heating coated thermochromic paper, or thermal paper as it is commonly known, when the paper passes over the thermal print head. The coating turns black in the areas where it is heated, producing an image. Two-color direct thermal printers can print both black and an additional color (often red) by applying heat at two different temperatures.

Quiz No. 5

Questions:
1. Differentiate between storage devices and storage media.
2. Identify the uses of tape, magnetic stripe cards, smart cards, microfilm and microfiche, and enterprise storage.
3. Describe the various types of flash memory storage: solid state drives, memory cards, USB flash drives, and ExpressCard modules.
4. Differentiate among various types of optical discs: CDs, archive discs and Picture CDs, DVDs, and Blu-ray Discs.
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

Quiz. No. 3

Answers:
1. Output is data that has been processed into a useful form called information. Four types of output are text, graphics, audio, and video. 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 nontext 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. An output device is any computer component capable of conveying information to a user.
2.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. 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. 

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. 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. 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. 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. 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. 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. 

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 No. 3

Questions:
1. Describe the four categories of output.
2. The characteristics of LCD monitors, LCD screens, plasma monitors, and HDTVs.
3. What are the components inside the systems units.
4. The components of a processor and how they complete a machine cycle.
5. Define a bit and describe how a series of bits represents data.
6. Identify the categories of application software.
7. Identify the key features of widely used business programs.
8. What are the advantages of using application software on the Web.
9. History of the Internet.
10. What are diferent storage devices.

Quiz No. 2

Answers:
1. 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. This kind of instrument also offers a button.  Light pen can be used on PDA's and also other kinds of portable computers.

 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.

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.

Digital Pen pen input devices found in several sophisticated graphic devices.  Generally electronic digital pen supplies much more performance compared to stylus pen.

2. Game Pad  is a general purpose game pad for use with {!IBM PC Compatible} computer games. The controller features 10 buttons and a special plug that allows two game pads to be connected to the same port. The unit is designed to be easily programmable for use with Windows 95 games.

Joystick This is to make a machine to perform in a certain way like the up and down, left and right arrows on you keyboard.

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. 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. 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

Video calling 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.

 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, 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.

 

 

 

5.

Quiz No. 2

Questions:
1. Describe various types of pen input, and identify other types of input for smart phones.
2. The purpose of various game controllers: gamepads, joysticksand wheels, light guns, dance pads,
and motion-sensing game controllers.
3. Explain how resolution affects the quality of a picture captured on a
digital camera.
4. Describe the uses of voice recognition, Web cams, and video conferencing.
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

Quiz:Answers

1. Whenever you enter data into your computer, it is referred to as Input. This can be text typed in a word processing document, keywords entered in a search engine's search box, or data entered into a spreadsheet. It can be something as simple as moving the mouse or clicking the mouse button or it can be as complex as scanning a document or downloading photos from a digital camera. The difference between Program, Command, and User response are as follows:

·         Program is like a recipe. It contains a list of ingredients (called variables) and a list of directions (called statements) that tell the computer what to do with the variables. The variables can represent numeric data, text, or graphical images. .

·         Command is a directive to a computer program acting as an interpreter of some kind, in order to perform a specific task. Most commonly a command is a directive to some kind of command line interface, such as a shell.

·         User Response is a plan of action aimed at accomplishing a clear business objective, with details on what work is to be done, by whom, when, and what means or resources will be used Programs are written either in one of high-level programming languages (such as BASIC, C, Java) which are easier but execute relatively slowly, or in one of low-level languages (assembly language or machine language) response times should be as fast as possible, but it is also possible for the computer to react so fast that the user cannot keep up with the feedback.

2. Keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches. Following the decline of punch cards and paper tape, interaction via teletype-style keyboards became the main input device for computers. Despite the development of alternative input devices, such as the following:

·         mouse

·          touchscreen

·         pen devices

·         character recognition

·         voice recognition

The keyboard remains the most commonly used and most versatile device used for direct (human) input into computers. a computer keyboard is a hard ware part of a computer which enables it to input numerical and alphabetical data a keyboard is used to type in data.
A desktop computer is a personal computer (PC) in a form intended for regular use at a single location, as opposed to a mobile laptop or portable computer.
Desktop and tower computers are two different styles of computer case that use desk space in varying ways. Desktop computers are designed to lay flat on the desk, while towers stand upright.
Prior to the widespread use of microprocessors, a computer that could fit on a desk was considered remarkably small. "Desktop" indicates a horizontally-oriented computer case usually intended to have the display screen placed on top to save space on the desktop. Most modern desktop computers have separate screens and keyboards.
Tower cases are sometimes incorrectly called desktop computers as some will locate them on a desk instead of on the floor under the desk. Cases intended for home theater PC systems are usually considered to be desktop cases in both senses, regardless of orientation and placement.

3. The different types of mouse and its description are as follows:

·         mechanical mouse requires a ball to move the cursor on the screen. To get more efficacies with this type of mice, a flat surface named mouse pads is necessary.

·         optomechanical or optical-mechanical mouse is a combination of the optical and the mechanical technologies. It uses a ball but detects the mouse movement optically. It is now the most commonly used with PC.

·         optical mouse uses a laser; precisely an optical sensor to help detecting the mouse’s moving. More expensive than the two other types, the optical mouses offer more precision and speed and even can be used on any surface.

·         wireless mouse which relies infrared, radio signals or Bluetooth to communicate with the computer. Using no cord, the wireless mouse contains a transmitter to send information to a receiver itself connected to the computer. The wireless mouse is usable from 2m to 10m of the computer.

·         cordless mouse uses the wireless communication technology (via infrared, radio or Bluetooth) to transmit data to the computer. And like the wireless, it doesn’t use any cord.

4. Three Types of Technology

Touch-screen technology falls into three categories: resistive, capacitive and surface wave. Each technology has strengths suited for specific applications.

·         Resistive

Ø  Resistive-type screens lack the clarity of other touch screens but they tend to be very durable and can be used in a variety of environments. Resistive-type screens are the most common in use today.

·         Capacitive

Ø  Capacitive screens are resistant to outside elements, making them very durable, and they still maintain a high clarity. Unlike resistive and surface wave screens, which can be used with stylus, capacitive panels must be touched with a finger.

·         Surface Wave

Ø  Surface wave touch panels are the more advanced of the three types, offering the highest clarity. But they are more easily damaged by outside elements.