Hardware

From TRCCompSci - AQA Computer Science
Revision as of 10:23, 6 March 2017 by Megan (talk | contribs) (Hardware Definition)
Jump to: navigation, search

Hardware Definition

Hardware is a collective term for the physical parts of a computer system; this also includes peripheral devices, not just the internal components. Hardware is the platform on which software is run, and is more invariable than software. However, the configuration of the hardware in the system can be changed by adding new adapters or cards to improve the system's capabilities. For example:
- Mouse
- Keyboard
- Motherboard
- Video card
Hardware can be simply defined as components of a computer system that can be touched and altered physically.

Other Terms

Devices

You will need to cover the principles of operation for the following devices:

RFID

RFID or Radio Frequency Identification is where a small device emits a small radio wave with a specific ID on it so that it can be detected. These are most commonly used in shops in an effort to stop theft.

Barcode Reader

A barcode reader reads a barcode and translates it into text that a computer can understand and decode. These are most commonly used in industry and shops to identify products quickly and easily.

Laser Printer

A laser printer prints by fusing toner (powdered ink) onto paper by heat. This means that the image is sharper as it doesn't use ink that would soak into the paper.

Digital Camera

A digital camera is a camera which encodes digital images and stores them for later reproduction

Secondary Storage Devices

Optical Disk

Optical disks are written with a laser which burns pits and lands onto the disk. To read pits and lands, the read/write head shines a laser onto the underside of the disk. Lands will reflect this light back to the photocell, which is registered as a 1. Pits reflect this light elsewhere, and are counted as 0s.

Hard Disk

A hard disk is made of a circular disk coated in a magnetic material called a platter, which spins at up to 10000 rpm. Each area of the platter can be independently magnetized or demagnetized by a read/write head to store a 1 or a 0. The read/write head is a tiny magnet that moves across the platter as it spins. One platter has two read/write heads - one to read the top of the disk, and one to read the bottom side. Data is written to the disk in concentric, circular paths called tracks. Each track is broken into sectors, and part of the hard drive stores a map of which sectors contain data and which are free.

Solid State Drive