Anglo-Frisian languages

The Anglo-Frisian languages are West Germanic languages, which include Anglic (or English) and Frisian. They are different from other West Germanic languages because of a number of sound changes. This is an old classification, which classified the Germanic languages into the Anglo-Frisian languages, and Germanic languages (such as German).
Since about the 1960s, the model is that there was a language called North Sea Germanic, which included all of these.