Electric Field

Electric field is defined as the electric force per unit charge. The direction of the field is taken to be the direction of the force it would exert on a positive test charge. The electric field is radially outward from a positive charge and radially in toward a negative point charge. 

where E= electric field, F= Force in Newton and q=charge in Coulamb

These two charges(positive & negative) produce 

field around it and called an electric field.

1- Positive   (+)

2- Negative  (-)

 Electric Field Unit

Therefore as SI unit of force is Newton and SI unit of the charge is Coulomb. 
Unit of electric field will be N/C.