Final answer:
The region of magnetic force around a magnet is known as the magnetic field, which affects charged particles and magnetized material without direct contact and extends into space as Earth's magnetosphere.
Step-by-step explanation:
The region of magnetic force around a magnet is referred to as the magnetic field. This field is where a magnet or magnetized material will experience a magnetic force without direct contact. The magnetic field is defined by the force on a charged particle when accounting for gravitational and electric forces. The magnetic field strength is proportional to the charge, the speed of the particle, and the strength of the magnetic field itself.
In addition to earthly magnets, Earth itself has a magnetic field which extends into the surrounding space. This region, known as the magnetosphere, traps charged particles and defines the zone where Earth's magnetic field is predominant over the solar magnetic field.