Why do all the planets travel around the sun in the same direction

Ah yes ! 
Also all of the asteroids.
And it's also the same direction in which most
     of the moons revolve around their planets.
And it's also the same direction in which
     the sun and most of the planets rotate.
Fascinating, eh Captain ?

Once you have noticed that fascinating pattern everywhere
throughout the solar system, it becomes a lot easier to understand
the concept of one gigantic, rotating cloud of dust and gas which,
over billions of years, shrinks and condenses to form the sun, plus
tiny bits and pieces of leftover material in orbit around the sun.

The question to your answer is illinois amigo