What Determines the Direction of an Electric Field?

[phy77]

I am a little confused with an electric field, Is it the kinda force between two particles positive and negative, or the force between two like charges? Then why is it that a positive charged particle can determine the direction of the field? i am a bit confused

thankyou

 

[rock.freak667]

Well an electric field is defined as any region in which a charged body experiences an electric force. Convention. The convention that physicists use is that they use a +ve test charge to determine the direction of an electric field.

[Electric field strength is given by E=F/Q]