Simply stated, Random Access Memory is a name applied to microchips designed to store and address information while a computer is actually using it. This is in contrast to the hard drive, which stores and accesses information semi-permanently (that is, until it is deleted).
RAM is volatile, which means that it needs a constant current supplied to it in order for it to retain information. Once the current is removed, the information disappears. This is why you have to save a document that you're working on before you shut off your computer. When you hit "save," the document is transferred from the RAM (temporary storage), to the hard drive or other non-volatile storage media (floppy disk, CD-RW, etc.). This is also one reason why it's important to save long documents periodically while you're working on them. If your computer experiences even a brief power interruption, all of the information stored in RAM will be lost.
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