# What is a Dependency

A dependency is an object a class needs to do its job. When a class creates its own dependencies with new, it's wired to them for good, and hard to test.

![Cheat sheet: What is a Dependency](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/be64beab662a430b9be62b4474960fd4.webp)

- Category: C#
- Level: Apprentice
- Tags: c-sharp, Dependency (oop), Dependency Injection (oop), OOP
- Updated: November 3, 2026

Source: https://www.ask-codey.com/cheat-sheets/dependency-injection-what-is-a-dependency-cheat-sheet