![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/7/79/Neighborhood_illust1.svg/640px-Neighborhood_illust1.svg.png&w=640&q=50)
Neighbourhood (mathematics)
Open set containing a given point / From Wikipedia, the free encyclopedia
For the concept in graph theory, see Neighbourhood (graph theory).
In topology and related areas of mathematics, a neighbourhood (or neighborhood) is one of the basic concepts in a topological space. It is closely related to the concepts of open set and interior. Intuitively speaking, a neighbourhood of a point is a set of points containing that point where one can move some amount in any direction away from that point without leaving the set.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/7/79/Neighborhood_illust1.svg/320px-Neighborhood_illust1.svg.png)