UNIT 2 - Buying a new computer

2. Devices

1a. Supercomputer

A supercomputer is the most powerful type of computer.
It can perform millions of calculations per second and is used for scientific research, weather forecasting, nuclear simulations, or space exploration.
Example: NASA or CERN use supercomputers.

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b. Mainframe

A mainframe is a very large and expensive computer used by big companies or governments to process huge amounts of data — like payroll, banking transactions, or flight reservations.
Example: Banks use mainframes to manage accounts.

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c. Workstation

A workstation is a high-performance computer for professionals who need more power than a normal PC — for example, graphic designers, architects, or engineers.
Example: A designer using AutoCAD or Photoshop.

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d. Desktop

A desktop computer is the typical home or office PC, placed on a desk, with separate monitor, keyboard, and CPU.
Example: The computer you use at school or in an office.

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e. Portable

A portable computer is designed to be moved easily. It usually refers to a laptop or notebook — smaller, lighter, and battery-powered.
Example: You take it to meetings or work remotely.

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f. Pen-based computer

A pen-based computer uses a stylus (digital pen) instead of a keyboard. You can write or draw directly on the screen.
Example: A tablet or a device for surveys or signatures.

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g. PDA (Personal Digital Assistant)

A PDA is a small handheld computer, popular before smartphones, used to manage contacts, calendars, and notes.
Example: PalmPilot or early HP iPAQ devices.