When a CPU
is looking for the next bit of code
to execute, the first place it searches is the speedy L1 cache
. If the data it needs exists in the cache, this is referred to as a "cache hit". Otherwise, the CPU must search the L2 cache
, then main memory
, and finally, in the worst-case scenario, the data will need to be paged from the hard drive
This term could also be used to refer to a similar situation in any other caching system, such as a browser cache.