Typically, five-star officers hold the rank of general of the army, admiral of the fleet, field marshal, marshal or general of the air force, and several other similarly named ranks. Five-star ranks are extremely senior--usually the highest ranks. As an active rank, the position exists only in a minority of countries and is usually held by only a very few officers during wartime. In times of peace, it is usually held only as an honorary rank.

What's the best answer to this question: is there such thing as a 5 star general?
yes