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- Hardware: inside a computer
Hardware: inside a computer
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Every computer, from a laptop to a games console, has the same main parts. Learn what each one does.
Input, process, output, storage
Memory: RAM and ROM
RAM (random access memory) holds the programs and data in use right now. It is volatile: it loses its contents when the power is turned off.
ROM (read-only memory) holds the instructions the computer needs to start up. It is non-volatile: it keeps its contents without power.
More RAM lets you run more programs at once smoothly.
ROM (read-only memory) holds the instructions the computer needs to start up. It is non-volatile: it keeps its contents without power.
More RAM lets you run more programs at once smoothly.
Secondary storage
Secondary storage keeps your files for the long term.
A hard disk drive (HDD) stores data magnetically on spinning disks. It holds a lot for the price.
A solid state drive (SSD) uses flash memory with no moving parts, so it is faster and tougher.
A USB memory stick is small, portable flash storage.
A hard disk drive (HDD) stores data magnetically on spinning disks. It holds a lot for the price.
A solid state drive (SSD) uses flash memory with no moving parts, so it is faster and tougher.
A USB memory stick is small, portable flash storage.
A student types an essay, sees it on screen, prints it and saves it. Name the hardware used at each stage.
- Typing: keyboard (input).
- Working on it: the CPU processes it, held in RAM.
- Seeing it: monitor (output). Printing: printer (output).
- Saving: secondary storage such as an SSD.
Answer: Keyboard (input), CPU and RAM (processing), monitor and printer (output), SSD or hard drive (storage).
Input devices put data in, the CPU processes it, output devices show results, and storage keeps data when the power is off. RAM is volatile; ROM is not.
The interactive lesson includes the diagrams for this topic.
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