What does sync mean?
In one sentence: Short for synchronise: devices swap their changes so every copy ends up the same.
A little more
Syncing means devices swap their changes until every copy matches. Your phone syncs photos with the cloud, a game syncs its save file, and a shared drawing board syncs every brush stroke.
Good syncing sends only what changed, not the whole thing, and copes with devices that were offline for a while and come back with a pile of changes.
It's a bit like… Two friends comparing their homework answers and copying over anything the other one has added.
See it in action
- BonusHow can two people draw on the same picture at once?Colour one picture on two pretend tablets, switch their Wi-Fi off and on, and compare three rules: last save wins, take turns, and merge square by square.6 min · interactive
- 12How does a game remember where you got to?Play a tiny game, switch the pretend tablet off and see what survives: working memory (RAM) versus the storage drawer, autosave checkpoints, a battery dying mid-save, checksums and cloud saves.6 min · interactive