Basic Concepts of Computer
CALL Fall, 2006
Computer in the elementary and high schools
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1. Hardware
Two main types of computers:
the Personal Computer or PC, a modern
variation of which is known as the Multimedia Personal Computer or MPC the Apple Macintosh - usually known as "the Mac" It must be capable of running the software that you need.
1.1 Main components of a computer
1. The computer itself: All that will be visible to
2.
3.
4. 5.
you is a metal case that contains all the essential electronic circuitry. The monitor The keyboard The mouse: A pointing device The disk drive: All computers have at least one internal disk drive for the storage of programs and data.
The computer itself
The computer itself
The central processing unit
The heart of every computer is the central processing unit or CPU, the computer's "brain". This is sometimes referred to as the central processor, microprocessor - or just processor. Ex. 286, 386, 486, Pentium
The computer itself
Speed
400MHz is faster than 350MHz MegaHerz GegaHerz=1000 MegaHerz
The computer itself
Inside the main casing of the computer are a number of microchips (technically known as integrated circuits) containing the computer's memory, which is usually referred to as RAM (Random Access Memory). RAM is a sort of working area in which the computer stores the programs it runs, performs its calculations and stores intermediate results. RAM is emptied the moment the computer is switched off. The computer therefore has to have some means of storing programs and data permanently. Key programs that enable the computer to operate are stored in another set of microchips known as ROM (Read Only Memory). ROM chips make up the computer's permanent memory, the place where it keeps the programs that tell it how to work. It is the combination of the central processor and the amount of RAM a computer contains that determines how powerful the computer is. RAM is measured in bytes. One byte can store one letter of the alphabet or one punctuation mark or one digit. For convenience, we usually measure memory in kilobytes=K (1000 bytes) or megabytes=MB (1,000,000 bytes). 128MB or higher is preferable if you wish to make use of audio and video material.
The computer itself
Video card: It is important to know what kind of video card your computer is equipped with, as this affects what the monitor can display e.g. VGA (Video Graphics Adaptor) or SVGA (Super Video Graphics Adaptor). CALL software often requires a video card that can display colour photographs and movies. It is therefore important that your video card can display a large number of different colours. Windows Control Panel : 640 x 480 800 x 600 1024 x 768 1280 x 1024 The lower the numbers, the lower the resolution. 800 x 600 is a fairly "safe" general setting for most software.
Monitor
--Display screen, screen: measured by inch: 14, 15, 17 The quality of the output on the display screen depends on the quality of the monitor itself, but it is also governed by the video card inside the computer. -- the LCD flat screen or LCD flat panel
Mouse
--important actions: point and click, double-click, left-click, right-click, clickand-drag, drag-and-drop --trackball --search for new types of mouse
Disk Drive
hard disk --MB, GB --Internal --External --Hard disks can contain vast amounts of data. --installed on the hard disk. Installation involves running an installation or setup program, icon floppy disk Flash drive
Disk Drive
floppy disk drive --MB, GB --Internal --External --Hard disks can contain vast amounts of data. --installed on the hard disk. Installation involves running an installation or setup program, icon
1.2 Multimedia PC (MPC)
A multimedia PC or MPC is basically the same as a standard PC, with the following additions: CD-ROM drive Soundcard Speakers / headphones Microphone DVD drive Webcam Most PCs on sale today are MPCs. An MPC is capable of handling text, pictures, sound and video - in any combination. MPCs can also play audio CDs and movies on DVD.
MPC
CD-ROM drive:Compact Disc Read Only
Memory. A CD-ROM is an optical disc on to which data has been written via a laser - a process often referred to as "burning a CD". CD-R, CD-RW CD Read/Write drive They are available in a variety of different speeds, the speed being described thus: 12x, 24x, 12-times, 24-times, etc.
MPC
Soundcard: an electronic circuit board
that is mounted inside the computer to control sound output to speakers or headphones and sound input from a microphone.
MPC
Speakers/headphones Speakers or headphones are essential for listening to sound recordings on multimedia CD-ROMs or audio CDs. Headphones can be integrated with a microphone - the so-called pilot's headset that is used in language laboratories.
MPC
Microphone:
--Important in the language lab DVD Drive and DVD player --The main advantage of all types of DVDs is that they offer very high quality video and sound. Their capacity - up to 25 times the storage capacity of a CD-ROM, which means that a DVD can comfortably hold a full-length movie. Webcam
1.3 Peripheral devices
A peripheral device - or simply peripheral - is any piece of hardware that can be connected to a computer. Ex: 1 Printer: ink and laser 2 Modem: converts computer data to a signal that can be transmitted over a telephone line. Dial-up and ADSL 3 Scanner: A device that copies hard copy information into digital data, translating the information into a form a computer can store as a file. To edit text read by an optical scanner, you need Optical Character Recognition (OCR ) software to translate the image into "real text" 4 Interactive whiteboard
2. Software: The programs that run on computers. For example, a wordprocessor is actually a computer program. More specifically, this kind of software is known as an application.
Operating System:
do housekeeping tasks, e.g. copying software from one disk to another, examining the contents of a disk or removing unwanted software from a disk. -- CUI: Character User Interface, ex: “copy a: c: ”, MS DOS (Microsoft Disk Operating System ) -- GUI: Graphical User Interface, Microsoft Windows -- It important to know which operating system your computer uses: e.g. Windows 95, Windows 98, Windows NT, Windows 2000, Windows XP.
Applications:Packages such as word-processors, databases
and spreadsheets - in fact any software package designed for a specific purpose - are known as a applications.
3. Networks
LANs and WANs ---- A LAN or Local Area Network is often confined to a single room or building, the computers or workstations on the network being connected by cable to a central server. If the cables can be run between buildings then the LAN can serve a whole school or university campus. --- A WAN or Wide Area Network can span any distance. Businesses with branches in several different towns or countries are often connected via a WAN.
Internet: The Internet is the biggest network of all. Such as, WWW.