Quiz #3

 1. Describe the four categories of output.

    

Monitors

Flat-screen monitors are more energy efficient than cathode ray-tube monitors. There are two major categories of monitors:

·        -Cathode ray-tube or CRT

·        -Liquid crystal display also known as flat-screen or LCD.

Both measure screen size diagonally and connect to the computer via USB port or a conventional printer cord. The flat-screen monitor uses less power and causes less eye strain.

Speakers and Headphones

Headphones are used to turn your computer into a telephone, stereo, or video game. Part of the sound card system that produces multimedia, speakers and headphones produce audio output. The range of audio equipment available to the average computer user is tailored to Messenger users, gamers, movie and video enthusiasts, and musicians. Most headphones also include a microphone for input as well.

Printers

Modern printers are advanced enough to publish detailed graphic arts and photos. Printers are used to make hard copies of computer output. There are three different kinds of printers.

·      -Dot matrix is the oldest and since it is slow and rather noisy compared to laser and ink-jet printers it is no longer widely used.

·       -Laser printers are the most expensive, but are fast and quiet

·       -Ink jet printers are inexpensive to buy, but the paper and toner consumption makes up for the cheap retail price.

Disks and External Drives

Portable memory sticks may have rendered CDs obsolete as output devices. CDs (which include rewritable CDs, DVDs), floppy disks and external hard drives are used as storage devices for data output. Data can be text, video, audio or graphics files. External memory drives are often portable depending on the size. Both disk drives and CDs can also be used as input devices.

2. Characteristics of:

• LCD Monitor- ultra-slim, stylish, full color display devices for the PC that fit in any part of the home or office.
• LCD Screens- lightweight, aesthetically appealing, energy efficient and long-term cost effective. 
• Plasma Monitors- produce rich colors along with very deep blacks, wide viewing
• TV’s are lit individually so the pixels can be completely turned off to display truck black colors. 
• HDTV’s- black level, brightness, contrast, color saturation, image processing, screen composition, tuners and cable card. 

 3. Components  Inside the System Unit:

• Processor
• memory
• adapter cards
• ports
• drive bays
• power supply
• motherboard
• chip
• Central Processing Unit
• Machine Cycle      

4. Components of a Processor:

• Control Unit
• Arithmetic/ Logic Unit (ALU)
• Register

 The machine cycle is the name of the four operations of the CPU. The first step is to 'fetch' the program instructions/data from the memory. The second step is to 'decode', which means translate the instruction into instructions. Step three is to 'execute', carry out the instruction. Finally step four is to 'store', write the result back to memory.

5. Define a BIT  and Describe  how a series  of  Bits  Represents a Data

When the user press any letter using the keyboard the electronic signal from that letter is sent to the system unit then the system unit convert 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.

6. Categories of Application Software:

• Personal productivity Applications
• Multimedia and Graphics applications
• Communications applications 
• Home and Educational

7.  The Key Features in Business programs in terms of software is editing and typing and other stuff knowing what letters to use like formatting.

8. Using web authoring software can help build web pages faster, an advantage if you are facing a deadline or a large project. There are several different types of web authoring software you can use to make great web pages without having to know all of the ins and outs of web page creation.

9. History  Of 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 NetworkNSFNET 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. (CSNET) and again in 1986 when
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. Different storage devices:

• Hard drive
• External Hard Drives
• network Attached Storage
• Optical Media Storage
• Flash Drives 

Quiz 321L IT Concepts & SAD Ans. 1&2

1) Define input and differentiate among a program, command, and user response.

Input is the term denoting either an entrance or changes which are inserted into a system and which activate/modify a process. It is an abstract concept, used in the modeling, systems design and systems exploitation. It is usually connected with other terms, e.g., input field, input variable, input parameter, input value, input signal, input port, input device and input file. A computer program is a sequence of instructions written to perform a specified task for a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. In computing, a command is a directive to a computer program acting as an interpreter of some kind, in order to perform a specific task. Response or output is the term denoting either an exit or changes which exit a system and which activate/modify a process. It is an abstract concept, used in the modeling, systems design and systems exploitation.

2. Identify the keys and buttons commonly found on desktop computer keyboards, and describe how  keyboards for mobile computers and devices differ from desktop computer keyboards.

Key types

Alphanumeric

Alphabetical, numeric, and punctuation keys are used in the same fashion as a typewriter keyboard to enter their respective symbol into a word processing program, text editor, data spreadsheet, or other program. Many of these keys will produce different symbols when modifier keys or shift keys are pressed. The alphabetic characters become uppercase when the shift key or Caps Lock key is depressed. The numeric characters become symbols or punctuation marks when the shift key is depressed. The alphabetical, numeric, and punctuation keys can also have other functions when they are pressed at the same time as some modifier keys.

The Space bar is a horizontal bar in the lowermost row, which is significantly wider than other keys. Like the alphanumeric characters, it is also descended from the mechanical typewriter. Its main purpose is to enter the space between words during typing. It is large enough so that a thumb from either hand can use it easily. Depending on the operating system, when the space bar is used with a modifier key such as the control key, it may have functions such as resizing or closing the current window, half-spacing, or backspacing. In computer games and other applications the key has myriad uses in addition to its normal purpose in typing, such as jumping and adding marks to check boxes. In certain programs for playback of digital video, the space bar is used for pausing and resuming the playback.

Modifier keys are special keys that modify the normal action of another key, when the two are pressed in combination. For example, <Alt> + <F4> in Microsoft Windows will close the program in an active window. In contrast, pressing just <F4> will probably do nothing, unless assigned a specific function in a particular program. By themselves, modifier keys usually do nothing.

The Enter/Return key typically causes a command line, window form or dialog box to operate its default function, which is typically to finish an "entry" and begin the desired process. In word processing applications, pressing the enter key ends a paragraph and starts a new one.

Navigation and typing modes

Navigation keys include a variety of keys which move the cursor to different positions on the screen. Arrow keys are programmed to move the cursor in a specified direction; page scroll keys, such as the 'Page Up and Page Down keys', scroll the page up and down. The Home key is used to return the cursor to the beginning of the line where the cursor is located; the End key puts the cursor at the end of the line. The Tab key advances the cursor to the next tab stop.

The Insert key is mainly used to switch between overtype mode, in which the cursor overwrites any text that is present on and after its current location, and insert mode, where the cursor inserts a character at its current position, forcing all characters past it one position further. The Delete key discards the character ahead of the cursor's position, moving all following characters one position "back" towards the freed place. On many notebook computer keyboards the key labeled Delete (sometimes Delete and Backspace are printed on the same key) serves the same purpose as a Backspace key. The Backspace key deletes the preceding character.

Lock keys lock part of a keyboard, depending on the settings selected. The lock keys are scattered around the keyboard. Most styles of keyboards have three LEDs indicating which locks are enabled, in the upper right corner above the numpad. The lock keys include Scroll lock, Num lock (which allows the use of the numeric keypad), and Caps lock.

System commands

The SysRq / Print screen commands often share the same key. SysRq was used in earlier computers as a "panic" button to recover from crashes. The Print screen command used to capture the entire screen and send it to the printer, but in the present it usually puts a screenshot in the clipboard. The Break key/Pause key no longer has a well-defined purpose. Its origins go back to teletype users, who wanted a key that would temporarily interrupt the communications line. The Break key can be used by software in several different ways, such as to switch between multiple login sessions, to terminate a program, or to interrupt a modem connection.

In programming, especially old DOS-style BASIC, Pascal and C, Break is used (in conjunction with Ctrl) to stop program execution. In addition to this, Linux and variants, as well as many DOS programs, treat this combination the same as Ctrl+C. On modern keyboards, the break key is usually labeled Pause/Break. In most Windows environments, the key combination Windows key+Pause brings up the system properties.

The Escape key (often abbreviated Esc) is used to initiate an escape sequence. As most computer users no longer are concerned with the details of controlling their computer's peripherals, the task for which the escape sequences were originally designed, the escape key was appropriated by application programmers, most often to "escape" or back out of a mistaken command. This use continues today in Microsoft Windows's use of escape as a shortcut in dialog boxes for No, Quit, Exit, Cancel, or Abort.

A common application today of the Esc key is as a shortcut key for the Stop button in many web browsers. On machines running Microsoft Windows, prior to the implementation of the Windows key on keyboards, the typical practice for invoking the "start" button was to hold down the control key and press escape. This process still works in Windows 2000, XP, Windows Vista and Windows 7.

The Menu key or Application key is a key found on Windows-oriented computer keyboards. It is used to launch a context menu with the keyboard rather than with the usual right mouse button. The key's symbol is a small icon depicting a cursor hovering above a menu. This key was created at the same time as the Windows key. This key is normally used when the right mouse button is not present on the mouse.

Quiz 321L IT Concepts & SAD Ans. 3&4

4) Various types of touch Screens and Explain how a Touch Sensitive Pad Works. 


A graphics tablet (or digitizing tablet, graphics pad, drawing tablet is a computer input device that allows one to hand-draw images and graphics, similar to the way one draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures.

A graphics tablet (also called pen pad or digitizer) consists of a flat surface upon which the user may "draw" an image using an attached stylus, a pen-like drawing apparatus. The image generally does not appear on the tablet itself but, rather, is displayed on the computer monitor. Some tablets however, come as a functioning secondary computer screen that you can interact with directly using the stylus.

Some tablets are intended as a general replacement for a mouse as the primary pointing and navigation device for desktop computers.
The first electronic handwriting tablet was the Telautograph, patented by Elisha Gray in 1888 . Elisha Gray is best known as a contemporaneous inventor of the telephone to Alexander Graham Bell.


The first graphics tablet resembling contemporary tablets and used for handwriting recognition by a computer was the Styalator in 1957. Better known (and often mis-stated as the first digitizer tablet) is the RAND Tablet also known as the Grafacon (for Graphic Converter), introduced in 1964. The RAND Tablet employed a grid of wires under the surface of the pad that encoded horizontal and vertical coordinates in a small magnetic signal. The stylus would receive the magnetic signal, which could then be decoded back as coordinate information.

Other graphics tablets a commonly known as spark or acoustic tablets, used a stylus that generated clicks with a spark plug. The clicks were then triangulated by a series of microphones to locate the pen in space. The system was fairly complex and expensive, and the sensors were susceptible to interference by external noise.

Digitizers were popularized in the mid 1970s and early 1980s by the commercial success of the ID (Intelligent Digitizer) and BitPad manufactured by the Summagraphics Corp. These digitizers were used as the input device for many high-end CAD (Computer Aided Design) systems as well as bundled with PC's and PC based CAD software like AutoCAD.

Summagraphics also made an OEM version of its BitPad which was sold by Apple Computer as the Apple Graphics Tablet accessory to their Apple II. These tablets used a magnetostriction technology which used wires made of a special alloy stretched over a solid substrate to accurately locate the tip of a stylus or the center of a digitizer cursor on the surface of the tablet. This technology also allowed Proximity or "Z" axis measurement.

The first home computer graphics tablet was the KoalaPad. Though originally designed for the Apple II, the Koala eventually broadened its applicability to practically all home computers with graphics support, examples of which include the TRS-80 Color Computer, Commodore 64, and Atari 8-bit family. Competing tablets were eventually produced; the tablets produced by Atari were generally considered to be of high quality.

In 1981, musician Todd Rundgren created the first color graphics tablet software for personal computers, which was licensed to Apple as the Utopia Graphics Tablet System.

In the 1980s, several vendors of graphics tablets began to include additional functions, such as handwriting recognition and on-tablet menus.


3) Different Mouse Types & Explain how to use a Mouse

Mechanical mouse has a small hard rubber ball underneath that moves against two rollers as it's passed across a flat surface. Mechanical sensors detect the movement of the rollers as an 'x' and 'y' axis and the cursor on screen is moved accordingly.

Optomechanical mouse works on the same principal. The rollers have wheels on the end of them with evenly spaced holes. As the wheels spin, a light-sensitive optical device counts the number of holes that pass by and convert those numbers to an 'x' and 'y' axis.

Optical mouse is more accurate or precise and has no moving parts. It uses a laser to detect movement and has to be paired with a special pad or mat that has an embedded optical reference grid.