ICT

Computer systems are used everywhere.They all have certain things in common:

They all process data

They are electronic

They are programmed

Computer systems can come in many forms.

Data means facts. Data has no meaning untill it has some context.

Computers are good at handling data.They take it as input and process it.

Information is data that has been interpreted in some way.

Hardware is the set of physical devices that make up a computer.

There is always at least one processor to carry out instructions.

All computing devices have memory where data/instructions are stored.

All computers need a power supply

Electrical supply is always at a low voltage

Voltage has to be stepped down by a transformer

Most small electrical devices have a battery so they can be recharged.

Software is the programs that are given to a computer.

A program is a set of instrucions to carry out.

PCs and other general purpose computers can be given many differnt programs.

Electronic gadgets often have programs installed on memory chips.

When programs are stored on flash memory chips, the can be changed when the software is updated.

General purpose computers usually run a wide variety of programs.

Most general purpose computers come under the category of microcomputers.

Desktop computers are housed in boxes. In offices the are connected via a network.

Laptops allow people to carry out usual activites on the move. They are have access to WiFi.

Tablet PCs are small computers with a touch screen.

Minicomputers are usually multiuser computers and are more powerful than microcomputers.

Mainframes are large, powerful computers used by big organisations from processing lots of data.

They need to be fast and reliable as they are used for many years.

Supercomputers are designed to perform high speed claculations involving huge amounts of data. They are very expensive.

People have been using PCs for a long tim to carry out standard office tasks and increase productivity.

Office software usually consists of the following; Word processors and desktop publishing, spreadsheets, database management,presentatino software and graphics.

Compression/decompression software is common on PCs.

They can be used to transfer large files over the internet.

Lossy compression is where some of the data from the file is removed.

Lossless is where no data from the file is removed.

PCs are widely used in all businesses.

Special purpose apps are available for a whole range of uses such as; stock control, booking system, retail system, medical records.

Mainframe computers are often used for mission critical systems. Mission critical systems are those that if fail can stop a business from functioning.

We all interact with mainframe computers when we; use an atm, make a tax return