Re: CAche,RAM,Auxilaary MEmory
The Non-Technical explanation
cache is part of the processor so the processor can communicate with it directly
ram is just chips of memory sitting on a motherboard, so the processor can communicate with it very quickly, but not as quickly as cache as cache is part of the processor and ram sits on the motherboard, near the processor.
hard disks are slowest because they are moving mechanical parts that have to be used to search for data. So a needle (or a metal arm with a little sensor at the tip) has to move up and down a spinning platter to read it. Takes time. Furthermore, they are connected by a cable, that is much longer in distance than the distance required for the processor to communicate with cache and ram.
so on that note, the new Flash Memory hard drives are much faster, because its basically ram connected by a cable. You don't have the overhead of moving mechanical parts.