Concepts

Explanation rather than instruction. Read these when something behaved in a way that surprised you and you want to know why, rather than when you are trying to get a specific job done.

The document model	Sketch, feature, part, body, and why there is only ever one solid
Constraints and freedom	What a degree of freedom is, and why redundant differs from conflicting
Profiles	How closed loops are found, and what makes one a hole
Rebuilds and speed	Why an edit takes time, and which edits take the most
Face references	How a sketch stays attached to a face, and why it sometimes cannot

Suggested order

If you are reading all five, that order is the one that builds on itself. The document model gives you the vocabulary; constraints and profiles explain the sketch half; rebuilds and face references explain the solid half.

If you are here for one thing, they stand alone.