1️⃣ Level 1: Primary cache is located in the processor, and is the fastest cache on the computer. Has its own CPU core.

2️⃣ Level 2: External cache is used to catch recent data accesses from the processor that were not held by Level 1. Level 2 is larger than one, but it is still not as fast. In old computers, it was located on the motherboard but is now also in the processor. Has its own CPU core.

3️⃣ Level 3: Used to catch recent data accesses from Level 2. Also located on the processor and again is larger but slower than level 2. Often referred to as a shared cache.