ELI5: Explain Like I'm 5

CPU cache

CPU Cache is like a really fast memory that your computer can access quickly. It helps your computer work faster and better by putting data that it needs to access often in a place that's easy to get to. For example, if you have a spreadsheet that you use all the time, the data from the spreadsheet can be stored in the CPU Cache, so it's easy for your computer to get to it.