Now that we've talked about moving up and down and side to side, you might be wondering about rotation.
We can also turn the drone, but to figure out how, we need to understand something else first.

What is Torque?

Torque is a way to measure the force that can turn something around an axis. This means that when our propellers spin, they create torque, which, if not taken into account, would make our drone spin out of control.

So why don't drones do that? Well, if you look closely at most drones, you will see that half of the propellers spin in a clockwise direction while the other half spin in the opposite direction. In our case, the pairs are across from each other on the diagonal. The drone flies steadily because these two different directions cancel out the torque.

Another thing to note is that each pair of these has a different propeller. One pair is the opposite of the other.
If this wasn't true, one pair would push air up and the other would push air down. This would cancel out the force, making it impossible for our drone to fly.

Since we now know what torque is, we can start to figure out how a drone turns.

Achieving Rotation!

If all the propellers on a drone need to have the same amount of torque, what would happen if they didn't?

You're right! After that, the drone would turn. So, to turn the drone left or right, we just need to slow down and speed up one of the diagonal pairs. The drone would then move either clockwise or counterclockwise, depending on which motors were sped up. Rotation is called yaw in the world of drone flight. This is part of what we call attitude, along with roll and pitch. Take a look at the diagram below to see this in action: