The 7475 is a TTL MSI circuit that contains four D latches, it is also known as 'quad bistable latch.' The 7475 is mostly used for temporary storing 4-bit nibbles of data. Any length of data can be stored by using more than one 7475 chip. When all four clock input pins connected to logic high clock pulse, input data is loaded into the D latches(each latch is D Flip-Flop) and appears at the Q output and remains there. After clock pulse goes logic low, the output at Q and Q' still holds input data till clock pulse changes it logic state back to 'High' and input data is changed.