In Anglo-American
law, one who dies without a valid
will is said to have died "intestate" ("without an estate (will)").
The law of course does not leave the property of such a person floating around without any owner. In the United States, the matter is handled by statute. The property of such a person (in most States) goes first to the surviving spouse; if none, to children or grandchildren; if none, to parents; if none, to siblings; if none, to closest living blood relatives. If none can be found, property escheats to the state.
Make a will. You're young? You think you won't die? Make a will. Automobiles are always with us. Not to mention other unforeseen circumstances.