Random access

Random access is the ability to access a random element of a group 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 computer storage on magnetic tape on spools (sequential) and hard disks (random access). 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).