The Hurwitz and the Lerch Zeta- Functions in the Second Variable, which is based on author's own research work, mainly deals with the study of the Hurwitz zeta Function as a function of the second variable, thereby connecting Riemann zeta function, gamma function, Bernoulli polynomials, Dirichlet L-Series and many other functions. In this book, the author has developed an approach based on Euler's summation fornula-cum-the basic fourier series, to deal with problems in number theory. In particular, the book gives a new approach to classical fourier theory. The book uses classical elementary methods subtly. Also the calculus of the Hurwitz zeta function as a function of the second variable has been developed.