Write briefly about the vested and contingent ownership?

[Jurisprudence] Ownership is either vested or contingent. It is vested when all the events essential to vest the property in the owner have happened and the owner’s title is already perfect. It is contingent when some of the events necessary to vest the property have only happened and the ownership can be vested only on the happening or non-happening of a specified uncertain event. In contingent ownership title is yet imperfect and is capable of being made perfect on the fulfillment of some condition. In the former case, he owns the right absolutely, while in the latter, he owns I merely conditionally.