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Programming concepts

Use the resources in this section to understand programming concepts in the C# language, including object-oriented programming.

  • page csharp/programming-guide/concepts
  • updated 10/10/2025

This section explains programming concepts in the C# language.

In this section

Title Description
Covariance and Contravariance (C#) Shows how to enable implicit conversion of generic type parameters in interfaces and delegates.
Iterators (C#) Describes iterators, which are used to step through collections and return elements one at a time.

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