Probate is the legal process by which ownership of the assets of a deceased person are legally passed on to the person's heirs.

If the deceased person had no will, the process is called an Estate Administration.  In the case the laws of the state (called intestacy) not the wishes of the deceased person, will decide who gets the assets.  If there cannot be an agreement about how to divide personal or real property, that property may need to be sold, often at a discount.

If the deceased person dies with a will, the will must be legally proven to be valid.  This is called Probate.  All of the persons who were entitled to inherit from the deceased person under the rules of intestacy (see above) must be put on notice of the probate proceeding and be given a copy of the will, even if they have been excluded.
Those persons who would have inherited under intestacy may then consent to the will being probated, or they can contest the will, hoping to undo the wishes of the will maker and receive what they would have had the person died without a will.

Probate