Memories differ in terms of the form of organization into word-organized memories and block-organized memories. Word-organized memories can have random access
, but also quasi-random, direct or implicit access. With random access, as with RAMs or ROMs, the access time to the memory elements
that canbe addressed in groups is always the same, which is related to the hard-wired addressing mechanism. Random access can also be content addressed as in associative memory
is one that is time addressed. In this access method, memory locations can be accessed in any order. Thus, the access times are variable. An example of memory with quasi-selective access isbubble memory
Implicit access is when the information is only available at an implicitly specified memory location.
FIFO memories and stack memories belong to this memory group.