Electric field lines indicate the direction of the electric force acting on a positive charge, which is a fundamental definition in physics. The electric field at a point is tangent to the field line that passes through that point. Field lines are always perpendicular to equipotential lines, as no work is done on a charge moving along an equipotential. The discussion also touches on the perception of field lines as abstract concepts, with some humor about their utility in visualizing electric fields. Overall, the conversation clarifies the relationship between electric field lines, electric forces, and equipotential lines.
