For a web tutorial on graphic lambda calculus go here. There will be detailed explanations concerning the three main sectors of the graphic lambda calculus, for the moment here is a brief description of them.

Sectors.

A sector of the graphic lambda calculus is:

a set of graphs, defined by a local or global condition,

a set of moves from the list of all moves available.

The name “graphic lambda calculus” comes from the fact that there it has untyped lambda calculus as a sector. In fact, there are three important sectors of graphic lambda calculus: