EX.TOPIC 1. 4-3-08.

Q. Describe THREE types of hardware and their uses and upload it into your websites providing preferences.

Answer:

1)Scanner
Purpose of a Scanner:

In computing, a scanner is a device that optically scans images, printed text, handwriting, or an object, and converts it to a digital image. Common examples found in many offices today are variations of the desktop (or flatbed) scanner where the document is placed on a glass window for scanning. Hand-held scanners, where the device is moved by hand, were briefly popular but are now less common due to the difficulty of obtaining a high-quality image. Mechanically driven scanners that move the document are typically used for large-format documents, where a flatbed design would be impractical.

2)speaker

speaker is an electromechanical transducer that converts an electrical signal to sound.

Purpose of a keyboard:

In computing, a keyboard is a peripheral partially modeled after the typewriter keyboard.

Physically, a keyboard is an arrangement of rectangular buttons, or keys. A keyboard typically has characters engraved or printed on the keys; in most cases, each press of a key corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence; other keys do not produce any symbol, but instead affect the operation of the computer or the keyboard itself. See input method editor.

A majority of all keyboard keys produce letters, numbers or signs (characters) that are appropriate for the operator's language. Other keys can produce actions when pressed, and other actions are available by the simultaneous pressing of more than one action key.

[Qouted from www.en.wikipedia.org]