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Rocky,
A buffer is normally just a section of memory used to connect two
systems of differing speeds. FIFOs are probably the
most
common, data is put into the buffer and taken out in the same sequence. Imagine
a buffer like a queue at a doctor's
office, people come in at varying speeds, take a number and sit down.
When the doctor is available the next number is
called
out and they can then see the doctor. The patients arrive at varying speed but
the doctor sees them in sequence
and at
his own speed. Best analogy I've got.
A
cache keeps copys of commonly requested items. A disk cache is the most common
example. When data is requested
from
the drive the cache unit passes on the data but keeps its own copy local to
itself. When this data is requested again
the
cache can use the copy in its local memory versus accessing the drive again. As
most memory is almost a million times
quicker to access than hard disks you can see the perform increase with a
good cache, ns access instead of ms.
Hope
this helps
Paul
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