Digital electronic circuits are usually made from large assemblies of logic gates, often packaged in integrated circuits. Complex devices may have simple electronic representations of Boolean logic functions. Digital electronics deals with the electronic manipulation of numbers, or with the manipulation of varying quantities by means of numbers.Digital systems deal only with the numbers 'zero' and 'one'.Undergraduate students studying digital electronics as one the optional subject will find this book useful to them. The book is written in simple and lucid language with suitable examples. One can find number of solved numerical problems on the topics covered in the book.