Eventual consistency.
Gossip: tell one person, and given a little time, everyone hears the news.
- Did you hear?1
A bit of news arrives and lands on one person right away. No waiting for the rest of town.
- 2
She passes it to a neighbour, who passes it on. The rumour spreads quietly in the background.
- Heard what?3
For a short while the town disagrees: some have heard, some haven’t. Ask two people, get two answers.
- 4
The news keeps hopping from person to person, reaching further with each retelling.
- 5
Soon everyone has heard the same thing. The copies have converged.
- 6
The trade: writes stay fast and nobody waits, in exchange for a brief window where copies differ.
Semicolony semicolony.dev/eli5/eventual-consistency/comic