In this book we consider the problems of estimating convergence and sum of series. Especially series with parameters is the remarkable one. In this book, we extend our remarkable results and offer wonderful methods to consider the convergence and sum of series with parameters.The book contains 4 chapters. Chapter 1 describes basic knowledge concerned with series. Chapter 2 deals with problems of estimating convergence and sum of series with parameters. Chapter 3 describes some hints helpful for the solution of the problems of chapter 2. Chapter 4 gives specific solutions to the problems of...