Computer Memory: Temporary Storage

Before your CPU can process any instructions you give it, those instructions must be stored somewhere, in preparation for access by the microprocessor. These instructions along with other data processed by your system are temporarily held in the computer's random access memory (RAM). All computers have some amount of memory, which is created by a number of memory chips. The more memory that is available in a machine, the more instructions and data that can be stored at one time.

Memory is measured in terms of bytes. One byte is equal to approximately one character in a word processing document. A unit equaling approximately one thousand bytes (1,024, to be exact) is called a kilobyte (KB), and a unit of approximately one thousand (1,024) kilobytes is called a megabyte (MB). A thousand megabytes is a gigabyte (GB).

Most computers today come with at least 128MB of memory, and it's not uncommon to find machines with 512MB or more. To enable your computer to run as many programs as quickly as possible, you need as much memory installed in your system as it can accept or that you can afford. Extra memory can be added to a computer by installing a new memory module, which is as easy as plugging a "stick" directly into a slot on your system's motherboard.

If your computer doesn't have enough memory installed, its CPU must constantly retrieve data from permanent storage on its hard disk. This method of data retrieval is slower than retrieving instructions and data from electronic memory. In fact, if your machine doesn't have enough memory, some programs will run very slowly (or you might experience random system crashes), and other programs won't run at all!