For removing fasteners at a faster rate by using a ratcheting wrench as opposed to the traditional combination wrench which requires you to remove the wrench and reposition it after the range if motion has been reached.
For tightening and undoing nuts and bolts.
A speed wrench ratchets back and forth.
That plug should not require an Allen wrench to remove it. Your 3/8" drive ratchet wrench should fit that plug perfectly.
A wrench is a tool used to turn a bolt or nut.
A monkey wrench is used much the same as an adjustable wrench. The original tool kit that came with a Model T or Model A Ford included a monkey wrench.
A torque wrench should not be used on any hitch type.
Line wrench
A pipe wrench, or an adjustable wrench, is used for any job which requires being able to adjust the wrench after inserting it into a tight or confined space, such as when attaching pieces of pipe together near a wall.
I usually tunk 'em all down with a speed wrench until they touch the shoulder and then get out the torque wrench.
15mm wrench
no.
Before torque wrenches you simply had to judge the amount of force you used by the 'pull' you exerted on the wrench.
A box wrench has a closed end and is used to tighten or loosen nuts or bolts.