Input, output and system diagrams

What comes out of an ICT system is largely dependant on what you put into the system to begin with.

ICT systems work by taking inputs (instructions and datadata: information without context, eg a list of students with numbers beside their names is data, when it's made clear that those numbers represent their placing in a 100 metre race, the data becomes information), processing them and producing outputs that are stored or communicated in some way. The higher the quality and better thought-out the inputs, the more useful the outputs.

Garbage In, Garbage Out (GIGO)

ICT systems cannot function properly if the inputs are inaccurate or faulty; they will either not be able to process the data at all, or will output data which is erroneous or useless.

GIGO is a useful term to remember in the exam - it can help explain many issues such as why validation is needed and why accurate data is valuable.

An ICT system diagram

A system is an assembly of parts that together make a whole. ICT systems are made up of some or all of the parts shown in the diagram. Various devices are used for input, processing, output, and communication.

ICT systems can be made of some or all of the parts shown.