---
tag: 0P7G9NGG2G
kind: concept
name: Faithful action
aliases: [effective-action]
msc: [20B05]
sources:
  - url: https://en.wikipedia.org/wiki/Group_action
    locator: Notable properties of actions
---

## Summary

A group action is faithful when only the identity element of the group fixes each point.
Then different group elements move the points in different ways.