---
tag: 0CQHFPGJ45
kind: concept
name: Topological space
aliases: [topology]
msc: [54A05]
sources:
  - url: https://en.wikipedia.org/wiki/Topological_space
    locator: lead section
same_as:
  wikidata: Q179899
  wikipedia: Topological space
---

## Summary

A topological space is a set together with a choice of subsets, called open sets, that obey simple rules for unions and intersections.
This structure is enough to define continuity, convergence, compactness and connectedness without a notion of distance.