GCSE Computer Science Revision

Secondary Storage:
RAM only stores data temporarily and ROM only stores a small number of instructions necessary to start the computer, so mist programs and data must be stored in secondary storage.

A backup is a secure second copy of data and files that is stored in another location. If the original files are lost or damaged, you can use the backup copy. When choosing the files’ size and the durability of the medium.

Optical media- uses lasers to read and write to and from the surface of the storage medium.

Flowchart:
Decision or choice: diamond
Input and output: parallelogram
Start and end of a program: rectangle with extra lines either side
start/end: oval

Process – this is where the data in-putted is used to convert the input into a readable form; the bar code read in can be processed to obtain a description of the product, the size of the product and the price, for example.

out on a till receipt with suitable calculations when the shopping transaction is completed.