Written by members of the Fortran 90 ISO and ANSI committees, this book is the source of the most important information about the powerful Fortran 90 programming language. It is organized so that it may be read beginning to end, but also so that particular topics may be studied directly. All of the important new features of Fortran 90 are covered with examples and case studies are used to illustrate the practical use of features. There are also simple problems designed to enable the reader to exercise their knowledge of the topics learned. Amongst the features of this book are: - free source form, new do and case constructs, recursion, modules, data structures, array processing, internal procedures, optional and keyword arguments, and nonadvancing input/output; - extensive examples of Fortran 90 programs; - case studies that illustrate the practical use of Fortran 90 features; - style notes; - extensive discussion of input/output facilities; - the complete syntax of Fortran 90.