Bight, Loop, Overhand
Knots are formed by using the bight-turn-tuck. Even the most complex knot can be figured out it you remember these terms.
The bight is formed by laying the end of the rope against the standing part or long end.
Loops, overhand or underhand, are just what their names say.
With these three turns, you can make any sort of knot.
A turn is wrapping the rope around something and a tuck is to insert the running end or a bight into a loop.