What is a node and how do I use them?

One of the fundamental building blocks in the program are vectors and vectors are two or more nodes joined by lines, Bezier curves, Arcs or a combination of these.  The position of the nodes, whether they are smooth or not and the position and strength of their associated control points will dictate the path (shape) that the vector follows between nodes.

You can see and use nodes after selecting a vector and pressing N to enter Node Editing mode.

Node Editing is a very powerful feature, allowing the user to precisely modify a drawing, troubleshoot problems with vectors, and help setup some types of toolpaths.