IC 7805 is a member of 78xx series of fixed linear voltage regulator IC. This regulator IC gives a constant output of 5v and input can be up to 24v (min. 7v). 5v is a basic voltage supply for most of the electronics circuit and getting a battery of exactly 5v is not that easy.
RoboElements has original IC. buy 7805 IC from RoboElements across India and give exactly 5v of supply to your project, IC, or any circuit.