---
tag: 0BSW4T7THS
kind: concept
name: Polar coordinates
aliases: [polar-coordinate-system]
msc: [51N20]
uses: [0XPR1E85W0]
sources:
  - url: https://en.wikipedia.org/wiki/Polar_coordinate_system
    locator: lead section
  - url: https://en.wikipedia.org/wiki/Polar_coordinate_system
    locator: Converting between polar and Cartesian coordinates
same_as:
  wikidata: Q62494
  wikipedia: Polar coordinate system
---

## Summary

Polar coordinates describe a point of the plane by two numbers. They are its distance $r$ from the origin and the angle $\theta$ from the positive $x$-axis to the ray through the point.
They simplify problems with circular symmetry, such as integrals over discs.

## Remarks

The polar form of a complex number is a related idea: see [[polar form|0BRXFNQ5JV]].