ELI5: Explain Like I'm 5

Optimistic replication

Optimistic replication is like playing with your friends at recess. Everyone wants to play together, but sometimes you have different ideas of what game to play or how to play it. So, you and your friends go off and play your own versions of the game.

In the same way, optimistic replication is when multiple copies of the same information are stored in different places. Like your friends playing different versions of a game at recess, these copies might be slightly different from each other.

But, here's the cool part: all of the copies are still considered correct, until proven otherwise. This is like how when you're playing at recess, all of the different versions of the game are fun and correct, until someone realizes they're not having as much fun as they could be. Then, you and your friends might decide to all play the same game together, and agree on the rules and how to play it.

Similarly, with optimistic replication, if someone realizes that there might be an error or mistake in one of the copies of the information, then all of the different copies compare their versions and decide which one is the most correct. It's like realizing that one of the versions of the game you and your friends are playing at recess has a broken rule, and everyone agreeing to play the "correct" version of the game from now on.

So, optimistic replication is like playing games at recess with your friends, where everyone has fun playing their own versions of the games, until it's time to make sure everyone is playing the same version of the game and following the same rules.