Law of conservation of angular momentum:

Objects executing motion around the point possess a quantity called as angular momentum. This is a significant physical quantity as all the experimental evidence indicates that angular momentum is rigorously conserved in the Universe: it can be transferred, but it cannot be destroyed or created.

The Conservation of angular momentum is a powerful law which encapsulates various aspects of motion as a result of the internal interactions. The conservation laws, including this one, addresses situations of motions, which otherwise cannot be dealt by direction application of Newton's law of motion. We encounter rotation, in which the rotating body is changing mass distribution and thus moment of inertia. For instance, a spring board diver or a skater displays splendid rotational acrobatics by manipulating the mass distribution about axis of rotation. Could we deal such kind of situation easily with Newton's law? Analysis of motions like these is best suited to the law of conservation of angular momentum.

Conservation of angular momentum is believed to be the counterpart of conservation of linear momentum as studied in case of translation. This perception is fundamentally flawed. As a matter of fact, this can be generalized law of conservation applicable to all the types of motions. We should realize that conservation law of linear momentum is a subset of more general conservation law of angular momentum. The angular quantities are all inclusive of rotational and linear quantities. As such, conservation of angular momentum is all inclusive. But, this law is regarded to suit situations, which involve rotation. This is the reason that we tend to identify the conservation law with the rotational motion.