# Normal

Normal may refer to:

## Education and teaching

• Normal school, a school created to train high school graduates to be teachers

## Technology

• Normal lens (photography), a lens of moderate focal length

## Mathematics

There are an extremely large number of unrelated notions of "normality" in mathematics. The following list is no doubt incomplete. See also the disambiguation pages for Normal form and Normalization.

### Mathematical Physics

• Normal or Wick order in Quantum Field Theory

### Topology

• Normal (or $T_4$) spaces, topological spaces characterized by separation of closed sets.