# Unit Test

A small automated check of one piece of code.

## What is **Unit Test**?

A **unit test** is a small automated check that one piece of code (a function or class) does what it should, in isolation, in milliseconds.

Level: Novice · [More Unit Testing terms at this level](https://www.ask-codey.com/glossary/subjects/unit-testing/novice)

Updated: September 27, 2026

## In other subjects

- [Unit Test in C#](https://www.ask-codey.com/glossary/unit-test-c-sharp)
- [Unit Test in Java](https://www.ask-codey.com/glossary/unit-test)
- [Unit Test in JavaScript](https://www.ask-codey.com/glossary/unit-test-javascript)

Source: https://www.ask-codey.com/glossary/unit-test-unit-testing