C# Using Keyword

Overview

The using keyword is used in the following 3 scenarios:

1. The using statement -- to ensure the IDisposible object is properly disposed
2. The using declaration -- to ensure the IDisposible object is properly disposed (C# 8)
3. The using directive -- to allow user to use types defined in a namespace without specifying the fully qualified namespace of that type.

Reference

https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/using