I will explain it in a way that you might understand.
Assume there is an NBA game going on, and in the broadcast truck, the director needs some kind of statistics to put on the screen, say - something like "how many points a player has".
The information is easy to access, the director sees the score board in the arena and can answer that "player X has 23 points" - that's called "accessing information from direct memory".
Sometimes the question is more complicated, like "where did player X on the other team go to college". The director does not have this information - but he shouts to the serfs in the truck "do you know where BlaBla McBlashphemy went to college" and someone in the truck knows - that's not directly from the director's memory, but he got it from local stored information in a somewhat harder to reach storage - that's called a "cache".
If the director needs some arcane information - he will need to call it from out of the truck or go to the library to find a book. That's getting it from "external storage".
In the example above,
@stampedehero gave us information from his picture cache, but it was slightly wrong answer. It's as if the director asked "who is our most clutch player" and the cache in the truck (
@HCP) came with a wrong answer (Kobe). A good director will understand that the correct answer was (lillard) and that the cache (
@HCP) is faulty.
