1. Thrust: This is the force that propels the rocket upwards. It's generated by the engines burning fuel and expelling hot gas out the nozzle.

2. Gravity: This is the force pulling the rocket downwards, towards the center of the Earth.

There are also other, smaller forces acting on the rocket:

* Air Resistance: This is the force of the air pushing against the rocket as it moves through it.

* Wind: If there's wind, it will exert a force on the rocket, potentially affecting its trajectory.

While the number of forces might seem simple, their interplay is complex and requires careful engineering to ensure a successful launch.