Simplify the following text for a Grade 7 native English-speaking person.
Original: In computer storage , disk buffer ( often ambiguously called disk cache or cache buffer ) is the embedded memory in a hard drive acting as a buffer between the rest of the computer and the physical hard disk platter that is used for storage .
Simplified: A disk buffer is a small amount of memory on a hard drive . Sometimes it is also called cache buffer , or disk cache , but these words should not be used , a disk buffer is not a cache .