Car contains one Engine Car uses Petrol Engine contains many SparkPlug Petrol is Fuel
EnterCar then StartEngine StartEngine then DidItStart DidItStart yes then DriveHome DidItStart no then WantToTryAgain WantToTryAgain yes then StartEngine WantToTryAgain no then Panic DriveHome then Done
Man has many Leg Leg has one Foot Foot has many Toe Man is Human Human is Mammal
Hominoidea has Hominidae Hominidae has Homininae Homininae has Hominini Human is Hominini Chimpanzee is Hominini Gorilla is Homininae Orangutan is Hominidae Gibbon is Hominoidea
Whether it's sketching a quick idea, or managing a model with hundreds of relationships, you edit the relationships instead of wasting hours on fiddly drawings.
Ain't nobody got time for that sh*t!