RANDOM-ACCESS

In computer science, random access is the ability to access an arbitrary element of a sequence in equal time. The opposite is sequential access, where a remote element takes longer time to access. A typical illustration of this distinction is the ancient scroll (sequential) and the book where any random page can be flipped open immediately. A more modern example is a cassette tape (sequential—you have to fast-forward through earlier songs to get to later ones) and a compact disc (random access—you can jump right to the track you want). The term  random access memory (RAM), however, is used for semiconductor chip memory circuits used in computers. (The term was also used to describe ferrite-core memory in early computers).
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