In the Namespace `System.IO` from `mscorlib.dll` there is the following field:

```
public static readonly char DirectorySeparatorChar

```

According to the documentation, it contains `\` on Windows and `/` on Unix. (<http://msdn.microsoft.com/en-us/library/system.io.path.directoryseparatorchar%28v=vs.110%29.aspx>)

My Question: Why is this field here? What is the usecase of it?

My assumption was always, that .NET is only supported on the Windows Platform.