Torque
Torque — measured in newton-metres (Nm) — is the twisting force an engine produces: what actually shoves you back in your seat and hauls a caravan up a hill. High torque at low revs means effortless overtaking without downshifting, which is why diesels and electric cars feel so strong in everyday driving. BHP describes how fast work gets done; torque describes how hard the initial shove is.
Example
A diesel with 400 Nm at 1,750 rpm will tow and overtake more easily than a petrol with the same bhp but 250 Nm at 4,500 rpm.