RAMThere are two main types of main memory used by a computer. These are called RAM (Random Access Memory) and ROM (Read-Only Memory).

ROM is a special type of memory that is built into the computer system. The contents of ROM do not disappear when the computer is switched off. Once a computer is switched on the ROM is accessed first. One function of ROM is to store the instructions for a computer to ‘boot up’. Booting up means that the operating system is located and loaded into RAM.

As well as being a place for the operating system to work from, the role of RAM is to make a computer or computing device as flexible and general purpose as possible. In order for any computer program to work it must be loaded into RAM before its instructions can be carried out.

RAM can be found inside a computer and consists of a number of computer chips that ‘plug in’ to the motherboard. RAM is used to temporarily store data and swap it between ‘volatile’ memory and your hard disk. It is volatile because, unlike ROM, if the computer loses power, anything in RAM will be lost, for example, if you are playing a game and the computer ‘crashes’ (turns itself off), you would lose your game, up to the point of the last ‘save game’, which had been saved to your hard disk. RAM is known as primary storage.

Other types of storage in a computer system are called secondary storage. The most popular form of secondary storage is a computer system’s hard disk. The hard disk or disks in a system are used to store all of the programs you have installed and all of the data that you have saved through using the computer, examples of data include saved games, documents, photos, music, etc.

Data Storage Activity

Task 1 – Revise

Use this link to the BBC BiteSize website and review the notes Data Storage.

Task 2 – Activity

Use this link to the BBC BiteSize website and watch the short interactive video on Data Storage.

Task 3 – Test

Use this link to the BBC BiteSize website and have a go at the Test.

Next: Computer Performance