The "king pin" is a steering part that controls the angles of the steering rotation.
While the correct term for a strut-based system is "steering angle inclination (SAI)", "king pin" inclination is still commonly used. Note that this angle includes both camber and caster.
A "strut" is a different discussion. A strut combines the spring and the shock absorber, but in a way different from a "coil over". A strut is a part of the system that controls the movement of the steering knuckle throughout its range as well as just absorbing shocks. Struts won't have ball joint on the bottom, because they'll be bolted directly to the steering knuckle, but there'll be control arms on the bottom that locate the bottom of the steering knuckle, and those'll have joints on it that may be ball joints.
There are a number of different ways suspensions are designed. The June 2017 issue of Car & Driver has a decent primer on suspension systems that shows a few of them. It's worth the price.
See the attached diagrams.