# Test Double

**Description**:

Fake object that help us simulate the situation required for a [unit test](https://blog.fiftywords.co/unit-test).

**Types**:

- [Mock](https://blog.fiftywords.co/mock)
- [Stub](https://blog.fiftywords.co/stub)

They are not mandatory for tests but are very useful for those cases where using a real object is complex for the situation we want to simulate.

[🇨🇴 Versión en Español](https://blog.cincuentapalabras.co/doble-de-prueba)