Anders Johansson wrote:
On Wednesday 23 June 2004 10.12, Koenraad Lelong wrote:
If we're going to be technical, hard drive secondary memory is also random access, and so is most of the ROM you have on chips in your machine. The opposite of RAM isn't hard drives or ROM it's sequential memory (tapes, et al.). So right now I have about 300 gibigytes of RAM in my machine :)
A couple of years ago, I read a book, about IBM's early computers. It was amazing what was used for memory back in those days. On method, was to use drum storage. With drums, you had to consider where the next instruction or data was located, in order to optimize access times. Another system used CRTs, similar to those used in radar, with the phosphor persistence being used for storage. There was also another system, that used columns of mercury, for acoustic delay lines. In the mid '50s, IBM developed core memory, which was much cheaper at only $1 per byte!