Stack Overflow Questions Tags Users Badges Unanswered Ask Question Ask for the explanation of types

I have read a document which tells me the following 4 things are done by the RAM embedded on disk driver controller. But I don't know what's difference between buffer and cache. Thanks!

RAM on disk drive controllers
1 firmware
2 speed matching buffer
3 prefetching buffer
4 cache

Well its like asking whats the difference between L1 and L2 cache in processors...
A buffer isnt big... just the size to bufferise correctly, a cache can be huge... the idea is having what is most accessed in cache to improve speed my not going to search on disk, and small enough to not loose too much time in searching when going to disk can be faster ( because data wasnt there... ) thus the importance of the cache algorithm...