

random access               Definition              random access




In the context of  computing, random access means that an entity,
such as  memory, can be  accessed at any  point, not just  at the
beginning.  This  means that all points within  memory can be ac-
cessed equally  quickly.  This contrasts  with sequential access,
in which entities must be accessed in a particular order, so that
some entities take longer to access than do others.

A tape  drive is an example of a  sequential access device, i.e.,
the order  in which  data are  read is dictated  by the  order in
which they stream past the tape head.  Random-access memory (RAM)
is an example of random access.  Hard disks and floppy disks com-
bine elements of random access and sequential access.

RAM, which usually consists of semiconductor integrated circuits,
is also strictly random access.  In this regard, the term ``RAM''
is   slightly  misleading;   a  more   accurate  name   would  be
``read/write  memory'',  to contrast  RAM  with read-only  memory
(ROM), which is also random access memory.

***** See Also *****

definitions, read-only memory


































COHERENT Lexicon                                           Page 1


