They can vary in design but most of them share two things in common - they are RTF rc airplanes, which stands for 'Ready To Fly', and they are electric powered.
These are the best two factors to look for when choosing a beginner's model.

Essentially, RTF means that the model needs no work done to it apart from some very basic assembly such as attaching the wing.
In fact, in the case of smaller beginner rc airplanes even this small job might not be necessary because the wing may be an integral part of the airplane.

So, what do you need to do to get a beginner's rc airplane airborne? Two things: