Why Memories?

Computer memories are one of the most fascinating areas of the short history of the technology. Mercury delay lines, Williams tubes, vacuum tubes, electrostatic memories, and magnetic cores are but some of the variations developed in the early years of computing.

Today, memories seem to be more or less standardized into three major kinds:

slow, cheap, long-term storage (mostly disks; various kinds of tapes and other archival media)
faster, more expensive storage that dies when the power goes off, called dynamic RAM or DRAM, which is the main memory of the computer
faster, even more expensive storage that is closer to the processing speed of the computer, called static RAM, or SRAM

What's interesting today is that you can buy a computer twice as fast every twelve to eighteen months in terms of processing speed. But the speed of ordinary DRAM memory is not keeping up -- in the not too distant future, we may start thinking of DRAM more the way we think of disks today: a relatively cheap way of storing a lot of information.

My major focus in this talk is on what's fun and interesting about memories. The bizarre, the intriguing, the plain surprising ideas that have gone into the design of computer memories. A peak into the future requires some technical content, but that will not be the main point of the talk.

Memories are Made of This 17:30 Thurs 12 September 1996
SHB5, Senate House, University of the Witwatersrand, Johannesburg, South Africa