# Feature flag

Concept · [Technical basics](https://ecosystem.samcarlton.com/technical)

Also called: feature flags, feature toggle, feature toggles, flag, flags

A switch in the code that [turns](https://ecosystem.samcarlton.com/turn) a feature on or off without [shipping](https://ecosystem.samcarlton.com/deployment) new code. [Teams](https://ecosystem.samcarlton.com/microsoft-teams) use it to test a feature with a few users first or turn it off quickly if it breaks.

**For example:** A team [turns](https://ecosystem.samcarlton.com/turn) on the new checkout for 5 percent of customers with a feature flag, watches for problems, then turns it on for everyone.

## Connects to (4)

- [Deployment](https://ecosystem.samcarlton.com/deployment): Putting the latest version of your app onto the live servers where real users can reach it.
- [Testing](https://ecosystem.samcarlton.com/testing): Checking that software does what it should, before your users find the problems for you.
- [Production](https://ecosystem.samcarlton.com/production): The live version of your app that real customers use.
- [Beta](https://ecosystem.samcarlton.com/beta): A version of the product released to a limited group of people so you can find problems before the full launch.

Map view: https://ecosystem.samcarlton.com/feature-flag