If you follow the hard drive market, you are probably familiar with names such as Raptor, Deskstar or Barracuda, which stand for hard drive families from various manufacturers. All of today's mainstream hard drives are based on rotating magnetic platters, allowing for relatively high capacities of up to 750 GB per hard drive. But the technology has limits, as the data transfer speeds did not increase much over time. As a matter of fact, hard drives are the slowest components in modern PCs.
Most attempts to speed up storage performance either use caches to store data that is used frequently, or they deploy faster memory solutions such as SDRAM or DDR-SDRAM. However, all of these require the steady supply of energy by means of buffer batteries or by sucking power out of the grid. Solid state hard drives based on Flash memory are similar to SDRAM-based solutions, but they are unaffected by power-related volatility issues, which plague SDRAM units. Data that is written to Flash stays - even throughout power interruptions.