---
tag: 0GJAJC6TNZ
kind: concept
name: Angle at a point
aliases: [unoriented-angle]
msc: [51M05]
sources:
  - url: https://en.wikipedia.org/wiki/Angle
    locator: lead section
---

## Summary

The angle $\angle ABC$ at the point $B$ is the opening between the rays from $B$ through $A$ and from $B$ through $C$. It is a number from $0$ to $\pi$, and it does not depend on the order of the two rays.