Controlling sketch geometry helps you prevent unintended changes by creating relationships between sketch entities. If all the geometry in a sketch is controlled, the sketch is fully constrained—the entities in the sketch cannot be modified without violating the controls, and you cannot add another control without creating a conflict with one that already exists.

The following section describes how you can use constraints, dimensions, and parameters to control sketch geometry. All three types of controls can be considered constraints since they all work to restrict the degrees of freedom in a sketch, but each control creates a different type of relationship between the selected entities.

The following topics are covered: