When you use a computer, information can be stored in one of two ways, temporarily or permanently. The temporary storage technical term is RAM which is an abbreviation for Random Access Memory. It is temporary because when you switch the computer off, or if it accidentally gets switched off because of a power failure, all the information is lost. To overcome this situation the other type of storage, permanent storage is used. This is usually called disk or hard drive storage. Generally when you enter information into a computer it is stored in RAM (temporary storage) until you tell the computer to copy the information from RAM to permanent storage, Disk Storage. This copying of information from RAM to Disk is called saving and is usually accomplished via a Save function on the File Menu.

Because usually, it is only possible for the computer to manipulate or process information in RAM it is also necessary to be able to copy information from a computers disk storage to RAM. This process is usually called Opening a file and is achieved by selecting Open for the file menu.