Constraints

There are 5 main types of constraints : Point (only mimics Translate attribute), Aim (where child aims at parent),Orient (only mimics Rotation), Scale (mimics uniform scale change) and Parent (mimics Translate and Rotate attributes). Unlike in Parenting in Constraints the first selected object becomes Parent, and also children can't move independently.

Unlike the parenting, constraints can be toggled on and off , it can be animated.