# Software Interfaces

A software interface is a contract between pieces of code. It lists what a class can do, never how, so code can use any class that keeps the contract. .NET is full of them, such as IEnumerable<T>.

![Cheat sheet: Software Interfaces](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/af4a4abe96944f93954f53d0d13a3ebc.webp)

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

Source: https://www.ask-codey.com/cheat-sheets/interfaces-in-csharp-software-interfaces-cheat-sheet