18.5.1—Electric potential at a point as the work done per unit positive charge in

Electric potential V at a point is work done per unit positive test charge bringing it from infinity, with zero potential at infinity.

Potential is scalar, so contributions add algebraically; electric field is a vector and requires direction.

A positive point charge gives positive potential, while a negative source gives negative potential relative to infinity.

Potential is not force per charge—that is field strength—and equal potential does not mean zero field everywhere.