Computer Assisted Language Learning (CALL) Overview of computers FITRIA ULFA 12267 K.1/2009

What is computer? Programmable machine

Computer is a programmable machine designed to automatically carry out a sequence of arithmetic or logical operations. Computer content of: hardware software

History of computer Started out 2000 years ago Improvement of computer until 1890 Invented in 1954 by Gottfried Wilhelm von Leibniz The first generation of modern programmed electronic computers was built in 1947. Building first digital computer was in 1962

Hardware is anything you can see, kick, drop or fall over, in other word which is a collection of electronic circuitry and other bits and pieces housed inside a case - and the essential devices you attach to it.

These are the two main types of computers : The Personal Computer or PC The Apple Macintosh - usually known as "the Mac" Both the above are available as desktop computers and laptop computers. More recently, so-called tablet computers have become very popular. A tablet computer is essentially a compact laptop computer that uses a touch screen instead of a keyboard for typing and to run programs.

Main components of a computer A personal computer consists of the following main components : The computer itself The monitor or display screen The keyboard The mouse The hard disc drive

b. RAM and ROM RAM  Inside the main casing of the computer are a number of microchips (technically known as integrated circuits) containing the computer's memory ROM  Key programs that enable the computer to operate are stored in another set of microchips The CPU and the RAM and ROM chips are located on the main electronic circuit board of a microcomputer, which is known as the motherboard.

Computer Central Processing Unit (CPU) The heart of every computer is the Central Processing Unit (CPU), the computer's "brain". In a modern computer the CPU is a single microchip.

c. Graphics card Graphics cards control the resolution of the text, pictures and video that appear on the screen. The resolution is determined by the number of small discrete dots, technically known as pixels, that make up the picture on your screen and therefore its definition or clarity

The monitor or display screen The monitor displays text, pictures and video and shows you the results of any actions you perform with the keyboard or mouse.

Newer types of monitors are of the LCD (Liquid Crystal Display) flat panel type - like many modern TV sets. They are much lighter, use less electricity and take up less room on a desktop. A more advanced form of technology for producing flat panel display screens is known as TFT (Thin Film Transistor).

The keyboard Computer keyboards are usually laid out in the same way as typewriter keyboards, plus a few extra keys that have special functions.

The mouse The mouse is used to control the position of the cursor on the screen and to initiate actions to be carried out by the computer. The mouse is attached to the computer by a cable and sits on a mat that has the function of providing better traction for the ball located inside the mouse.

Disc drives Hard disc drive  is a sealed unit consisting of a rigid magnetic disc enclosed within a metal case which is mounted internally in the PC. The storage capacity of a hard disc is measured in megabytes (MB) or gigabytes (GB).

b. Floppy disc drive These drives were used to read data and programs stored magnetically on a portable disc enclosed in 3.5-inch square plastic case. Floppy discs were used mainly for carrying small amounts of data around from one location to another, e.g. a Word document or a PowerPoint presentation c. External hard disc drive External hard drives are often used for backing up essential programs and data

d. Flash drive These portable storage devices - also referred to pen drives or memory sticks - are around 3cm to 5cm in length and look like a small flat pen

Software is the word used to describe the programs that run on computers. For example, a word-processor is actually a computer program - or a suite of programs - a set of instructions that make the computer behave as a word-processor. More specifically, this kind of software is known as an application.

Contents of Section: Operating systems Applications

Operating systems  a suite of programs that is supplied with every computer to facilitate what are generally known as housekeeping tasks e.g. copying software from one disc to another, examining the contents of a disc or removing unwanted software from a disc. Using a mouse, you cause the cursor to zip around the computer screen and point to an icon.

b. Applications Packages such as word-processors, databases and spreadsheets - in fact any software package designed for a specific purpose - are known as applications.

Computer has the ability to : Perform computations and making logical decisions Perform the information processing cycle with amazing speed. Store huge amounts of data and information. Communicate with other computers.

THANK YOU