What are electric lines of force ? What is its importance ?

Explanation

Electric lines of force are the path followed by a unit positive charge in an electric field, if it is free to do so and the tangent at any point (say P) gives the direction of electric field at that point.
Importance. Drawing electric lines of force helps us to visualize to some extent the electric field in some region of space. Of course lines of force can only give us partial information about the nature of the electric field produced by given sources, but still be valuable. While we could put an arrow on each line of force to indicate the direction of electric vector at each point on it, the line cannot indicate the magnitude of the electric vector.