Atomicity (database systems)

Atomicity is a big word that means doing things all at once. Imagine you're playing with some building blocks and you want to build a tall tower. You can't stop halfway through and take a break – you'll have to finish building the whole tower before you can take a break.

In a database system, atomicity means that if you want to make a change to some data, like adding a new name to a list, the database will either do the whole thing or none of it. It won't do half of the change and then stop halfway through.

This is important because if the database were to stop midway through a change, like if the power went out, the data could be left in a state where it's partly changed and not correct. But by making sure that changes are atomic, the database ensures that the data is always in a correct state – either the change was made completely, or it wasn't made at all.