Repeater is a communications device that amplifies the data signal in order to extend the transmission distance. Repeaters work at layer 1 of the OSI model.
Bridges connect 2 n/ws that use the same technology (eg. Ethernet and ARCNET).
The use of bridge increases maximum possible size of n/w.
Unlike a repeater which simply passes all signals it receives ,a bridge selectively determine the appropriate segment to which it should pass a signal. It does this by reading the address of all the signals it receives.The bridge reads the physical location of the source and destination computer from this address.