Essentially the pagefile.sys (which at a high level is a massive memory mapped file that Windows uses for virtual memory) gets stored on a flash drive. It very

Essentially the pagefile.sys (which at a high level is a massive memory mapped file that Windows uses for virtual memory) gets stored on a flash drive. It very much helps the overall responsiveness of a computer that doesn't have enough RAM to do without a pagefile.sys -- especially if they have a slow hard drive (I inadvertently installed Vista on a slow computer and this helped quite a bit). ReadyBoost is different from PreFetch (they are features you can turn off/on independent of each other) which I believe you are referring to when you mention "pre-loading". The wikipedia article is decent: http://en.wikipedia.org/wiki/ReadyBoost http://en.wikipedia.org/wiki/ReadyBoost