Cache Memory
In plain terms
Small, fast memory close to the CPU storing hot data.
Going deeper
Cache memory holds frequently-used data and instructions near the CPU to avoid slower main-memory access, boosting speed. It bridges the CPU-RAM speed gap.
Under the hood
Multiple levels (L1/L2/L3) trade size for speed; cache misses force slower memory access.
Examples
L1/L2/L3 cache, CPU performance, cache hits/misses, locality of reference.
Think of it like...
Like keeping your most-used tools on the bench instead of walking to the storeroom.