This is a text that provides a modern and comprehensive material on the subject matter which includes applications of DSP in areas like Speech Processing, Radar, Image processing etc. The book starts with the basic concepts of digital signals and hardware necessary for generation and processing of such signals. It is assumed that the reader has had adequate exposure to Digital electronics, Advance calculus, Laplace and Fourier transform. Hilbert transorm, Elemens of the theory of random processes, Convolution integral etc., have been discussed briefly. Discrete-time signals, Z-transforms, Discrete Fourier transforms, and Discrete Hilbert transform, are treated as is relevant to DSP. Theory and design of various (LP, HP, BP, BR) kinds of IIr and FIR filters have been discussed. A full chapter has been devoted to fast Fourier transform (FFT), FFT algorithms in FORTRAN as well as in C language is provided in the Apendix. Review qustions, and an equal number of homework problems with anwers and approximately 300 solved examples are included. Some 200 (approx.) Multiple Choice Questions are a special feature of this. With its comprehensive yet compact coverage and simple motivating presentation, the book is an ideal text for the Electronics and Computer Engineering students.