Digital Communications‎:‎ Theory‎,‎ Techniques and Applications 2e is written for students of undergraduate degree programs in engineering for a course on digital communication‎.‎ The second edition of this book treats spread spectrum communication techniques as an exclusive chapter‎.‎ The book starts from the basics of signals and systems‎,‎ builds the preliminary concepts through the chapters on probability and random process‎,‎ and information theory‎,‎ and then describes the core concepts such as digital coding‎,‎ multiplexing and multiple access‎,‎ modulation techniques‎,‎ demodulation‎,‎ error control coding and spread spectrum communication‎.‎ The last chapter illustrates the concepts learnt in the earlier chapters through certain applications in optical‎,‎ satellite‎,‎ and wireless communication domains‎.‎