What is a couple, its properties and uses?

What is a couple, its properties and uses?

A pair of equal and opposite forces with different lines of action is known as a couple.
properties:- A couple produces rotation without translation. Moment of couple is product of magnitude of Forces and the distance between them. Moment of couple is independent of the origin of the forces or reference point.
Uses:- couple is used to rotate the object without giveing any translational motion. For example when we open the lid of a bottle by turning it, our fingers are applying a couple to the lid.