Forces
If you've ever gone out on a windy day, you may have felt like you were pushed by the wind. If you've ever jumped up(which you most likely have), you've felt like you were pulled down to the ground. If you've ever been in a car and the car suddenly sped up or slowed down, you may have felt your body jerk.
These are examples of fundamental interactions known as forces. Forces are arguably the most important interactions you can comprehend. They're the reason why the molecules you(and everything else) are made of stick together. They're also the reason why planets like our very own Earth rotate around the Sun.
To learn more about forces, click on any of the links below:
Drag
Lift