.NET - CLR version vs. Framework version

Is it CLR version or Framework version? What's the difference?

The CLR is the .NET Runtime.
The Framework is the .NET Class Library.

CLR version numbers are of the form:

1.0 | 1.1 | 2.0 | 4.0

Framework version numbers are of the form:

1.0 | 1.1 | 2.0 | 3.0 | 3.5 | 4 | 4.5 | 4.5.1 | 4.5.2 | 4.6 | 4.6.1 | 4.6.2 | 4.7

Typically, there is a 1-1 correspondence between a Framework version and a CLR version. E.g. Framework 4.x, is usually built on CLR 4.x.
There are exceptions. Framework versions 3.0 and 3.5 were built on CLR version 2.0.