This is our second KS3 ICT quiz on data storage. Computer data storage provides one of the core functions of the modern computer, that of keeping valuable information safely and accurately. Each time data is transferred, it is possible that it may be changed slightly due to defects in the system. We say that data altered in this way has been corrupted. When saving any data, it is always good to have a separate back-up copy. This could be on an external hard drive, USB flash memory or something like a CD-ROM.
Data storage is normally organised into records and fields in a database, text files or images. The simplest database is known as a flat file. This is a file in which the data is stored in one single table. More complex databases contain data in different tables and are called relational databases. These are very useful where one item can have several different pieces of data stored about it e.g. the different books borrowed from a library by one person.