What's an ansi class in C#?

I started using reflection in my project.

When I create a type and I want to specify the TypeAttributes, I have two options: AnsiClass and Class. They are both set to 0 in the enum TypeAttributes.

1- What's an ANSI Class (I noticed that, it's related to the LPTSTR, but I didn't understood well enough)?

2- What's the difference between an AnsiClass and a Class when I use Reflection.