作者Xforce

http://www.seagate.com/support/kb/disc/tp/cache.html

Caching, in effect, anticipates requests for certain data (usually the next in line) and draws that data into memory before the system needs it. Because the caching program reads information into memory before it is needed, it is often also called a Read Look-Ahead Buffer. Caching occurs at many levels within a company, so it is not necessary for the cache to reside with the host computer's main memory. A disc drive can handle the caching for itself, leaving the host computer free from the burden of managing the cache for that device.
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