Computer Systems

Question	Answer
INPUT	The data which is entered in to a computer/device.
PROCCESSING	This is what goes on inside a computer when it makes your data able to be released.
OUTPUT	Output is the proccessed data that is released. The output device could be: monitor, speakers, printers.
COMPUTER SYSTEM	A combination of hardware and software components that allow input, processing and output of data.
HARDWARE	The physical components that make up a computer system.
SOFTWARE	The programs that run on a computer system.
RELIABILITY	How far you can depend on the computer system being available when you need it. Usually measured in terms of availability.
AVAILIBILITY	The proportion of time that a system is operational, usually expressed as a percentage over a period of time. E.g. 95% measured over one year.
MTBF	Mean Time Between Failure: a measure of availability often quoted by hardware manufacturers. Eg 2.56 years between failures means, on average, the hardware can be expected to last 2.56 years before it goes wrong.
REDUNDANCY	Spare hardware components are built into a system so that, in the event of a component failing, the system can swap over to the spare one.
DISASTER RECOVERY	Where a company has plans to replace a system quickly if there is a catastrophe (fi re, fl ood, bomb etc). Designed to minimise the time the system is down.

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	Created by EmilyWilliamson almost 9 years ago