Inheritance is the legal process of transferring a deceased person's property, debts, and titles to their heirs, governed by rules that vary widely across societies and legal systems. Succession can occur through intestate succession (statutory rules when there is no will) or through a valid will, which often requires notarization or other legal formalities to be enforceable. A key distinction exists between common law jurisdictions, which typically require formal probate, and civil law systems, which often allow heirs to automatically acquire ownership through the principle of saisine. While the term "heir" technically applies only to those inheriting under intestacy laws, individuals named in a will are called beneficiaries (or devisees, legatees, or recipients of bequests), and a person can be completely disinherited, as famously seen in comedian Jerry Lewis's will, which excluded his six children from his first marriage. Historically, inheritance customs have ranged from patrimonial (male-only) and matrilineal systems to modern egalitarian laws, with religious traditions like Jewish law (based on the Law of Moses) granting the firstborn son a double portion. Ultimately, a person only becomes an heir upon the death of the deceased, at which point their exact identity is determined, and the practice is sometimes compared to nepotism.