Different Computer Systems

1. Mainframe Computer

Movie 1. Mainframe Computers.

20 A mainframe computer is a computer system with:

• very powerful processors
• lots of backing storage
• large internal memory.

Mainframes are designed to process large volumes of data at high speed. They are used by large businesses such as

• banks and mail-order
• companies as well as by large
• organisations such as universities.

Mainframe computers can also multi-task by running more than one program at the same time time. This is known as multi-programming and with more memory has become possible on desktop and laptop computers.

 

2. Desktop Computer

Movie: 2. Desktop Computers.

A desktop computer is the most common kind of PC. It is a collection of a number of different hardware devices. This type of computer is sited permanently on a desk because its design means it cannot be easily moved. The common components of a desktop PC are:

• the system unit containing the processor and main memory
• monitor
• keyboard
• mouse
• hard disk drive
• floppy disk drive
• CD/DVD drive
• speakers.

 

3. Laptop or Notebook Computer

Movie: 3. Laptop Computers.

A laptop computer is a small, light computer that you can easily carry about with you. It can be powered by battery or mains power. A laptop computer has a keyboard, and comes with specialised input devices, for example trackballs, touch pads or track points. They are needed because laptop computers are often operated in places where it is impracticable to use a mouse.

For output the laptop has an LCD or TFT screen and a set of small speakers.

‘Laptops’ are often as powerful as desktop computers and run the same range and type of software.

People use laptops for working when they are on the move, going to meetings or attending courses.

Many businesses are replacing desktop PCs with special plug-in workstations designed round laptop computers because of the flexibility they offer.

 

4. Palmtop Computer or Personal Digital Assistant (PDA)

Movie: 4. Palmtop Computers.

This type of computer is increasing in popularity, and is often called a Personal Digital Assistant (PDA).

A palmtop computer is small enough to fit in your pocket.

It combines a lot of capabilities, including organiser features (such as storing contact numbers, names and addresses, etc.), e-mail and wireless internet access.

Palmtop's have small keyboards and most let you open menus and select icons by using a special pen or stylus. Most let you enter data by writing with the stylus. They are powered by batteries and store their data on removable memory units called flash cards.

You can run a wide range of software on palmtop's, for example simple word processing, database and spreadsheet software as well as useful applications such as electronic diaries. Many modern palmtop's:

• are converging with mobile phones to let you access the internet
• have wireless communications to let you access your local area network.

 

What you have to do!

In a new Word document, enter a heading Computer hardware and save the file. - 9this will form your notes for this topic)

1. Watch each of the movies in turn and;
2. answer the following questions.
   1. Why do large businesses such as banks use mainframe computers?
   2. Describe the components of the desktop computer you use in school or at home.
   3. Complete this table comparing a desktop with a laptop.
      
      

      	Desktop	Laptop
      Output	Ordinary Monitor	LCD/TFT
      Backing Storage	Hard disk, floppy disk, CD/DVD Drive
      Power Source	Mains Power
      Portable	No

      
      
   4. Name three types of software that run on palmtop's.
   5. Why are palmtop's useful?

       

What you should be able to do!

1. Describe different types of Computer System..

2. Give some of the advantages and disadvantages of each type of computer System.

3. Recommend a particular computer system for given situations.

 

Continue to 3. Input Devices