Difference between revisions of "Random access"

From Computer History Wiki
Jump to: navigation, search
(A decent start)
 
m (+cats)
Line 6: Line 6:
  
 
{{semi-stub}}
 
{{semi-stub}}
 +
 +
[[Category: Hardware Basics‎‎]]
 +
[[Category: Device Basics‎‎]]

Revision as of 04:22, 13 December 2018

Random access refers to memory (either main memory, or secondary storage) which has the characteristic that two sequential (in time) operations can go to disparate addresses without significant delays; in sequential access memories, only successive operations to following locations can be done without a time penalty.

Several early main memory technologies (delay lines and drums) did not have this characteristic, although the short-lived Williams tube did.

In secondary storage, magnetic tape is sequential only; disk is a mixture of sequential and random (although fixed-head disks are sequential only within a track; head selection can be random.)