Which of these characteristics of a missile differs from a rocket?

A rocket has a propulsion system to make it fly into the air. A rocket can be a missile but a missile does not have to be a rocket. The ancient Romans used catapults (called ballista) to launch missiles made of rocks or stone at the enemy. Medieval soldiers threw spears as missiles at the enemy.

Today missiles are launched by a rocket. A launched missile that follows the path determined at launch time is a ballistic missile as in an ICBM (Intercontinental ballistic missile). The rockets get it going at some speed and direction. If it has some sort of guidance mechanism built in such as a gyroscope or directional rockets, it would be called a guided missile.
missiles have a guidance system