The bunnyhop is a basic skill that allows you to lift both wheels off the ground simultaneously to clear obstacles. It's definitely on the more basic side of the skills spectrum, but it is one that you will use forever throughout your riding no matter what level you are at. It's used for so many things on the trails, from hopping rough sections, to jumping, to unweighting in strategic sections. I prefer to teach this technique to students by starting with flat pedals and moving onto clips later