Forwards bias:
In diode if it allows flow of current in one direction then it is called forward bias.
Reverse bias:
If diode does not allows flow of current in other direction then it is called reverse bias.
This is a characteristics of semiconductor diode {pn junction}.In forward biasing here we connect p to positive terminal and n -ve terminal when external voltage is aplied in such a direction thatcancels out potential barrier thus permitting current flow. A condition in which a PN junction allows current to flow in one direction only.
In diode we have to connect the p-type to the +ve terminal and n-type to the -ve terminal
Positive positve or negative negative = frwd bias
Positive negative or negative positive= reverse bias
