B,E and G field

Similarities:
1. the three kinds of field are represented schematically by [lines of force];
2. the three kinds of field have actions that extend to infinity.
3. the inverse square law holds for the three kinds of field arising from a point mass/charge/magnetic pole.

Differences:
1. the three fields produced by objects of different physical nature, i.e. gravitational field from mass, electric field from charge, and magnetic field from magnetic pole or electric current(i.e. moving charge).
2. a time varying magnetic field produces electric field and vice versa; but a time changing gravitational field produces nothing.
3. magnetic field lines tend to form closed loops, but not the other two fields.