In computing, '''[[sequential access]] [[computer ioytfgrjjmemorymemory|memory]]''' ('''SAM''') is a class of [[data storage device]]s that read stored data in a sequence. This is in contrast to [[random access memory]] (RAM) where data can be accessed in any order. Sequential access devices are usually a form of [[magnetic storage or optical storage]].<ref>{{cite|title=difference between sequential and random access operations|url=http://kb.sandisk.com/app/answers/detail/a_id/8150/~/difference-between-sequential-and-random-access-operations}}</ref><ref>{{cite|title=Turing machine model of computation sequential access memory|url=http://www.docfoc.com/1-lecture-13-turing-machine-model-of-computation-sequential-access-memory}}</ref>
While sequential access memory is read in sequence, arbitrary locations can still be accessed by "seeking" to the requested ___location. This operation, however, is often relatively inefficient (see [[seek time]], [[rotational latency]]).