Somerville Bowline
It is one of the best knots to learn.
It starts off as a simple single columne tie.
A variation can be used in line if one end is already tied up.
And another variation can be used to make a quick double columne tie.
Pros: Easy to learn, very versetile, can be used as a quick release.
Cons: Very bulky, not the most visually appealing version.
Some good turorials are made by
The Dutchy ,
Crash restraints.