20.1.1—A magnetic field is an example of a field of force produced either by moving

A magnetic field is a region where magnetic poles, moving charges or current-carrying conductors experience magnetic force.

Separate field source from test object: stationary charges do not feel magnetic force, while currents and moving charges can.

A current in a wire creates a field around the wire; a nearby compass aligns with the local field direction.

A magnetic field is not simply another name for electric field, and it does not act on every charge regardless of motion.