5.2.1 Cache Memory (L1, L2, L3)

Cache memory is like the CPU's personal, super-fast mini-notepad. It's tiny but incredibly quick. The CPU stores data it uses very often in cache, so it doesn't have to go all the way to the main memory, which is slower. There are usually different levels of cache:

L1 Cache: This is the fastest and smallest cache, right inside the CPU.
L2 Cache: A bit larger and slightly slower than L1, but still very fast.
L3 Cache: Even larger and a little slower than L2, often shared by multiple parts of the CPU.

The more data the CPU finds in cache, the faster your computer can run!