Why do planets revolve around the Sun and not fly away into space?

Planets revolve around the Sun because of the gravitational force. The Sun has a very large mass, so its gravity pulls all the planets toward it. At the same time, planets are moving forward in space with high speed. The balance between the forward motion of the planet and the pull of the Sun’s gravity keeps the planets moving in fixed paths called orbits. Without the Sun’s gravity, planets would fly away into space.