Numerous examples and exercises highlight this unified treatment of the Hermitian operator theory in its Hilbert space setting. Its simple explanations of difficult subjects make it intuitively appealing to students in applied mathematics, physics, and engineering. It is also a fine reference for professionals. 1990 edition.
Taste in math textbooks is highly personal and depends on your idiosyncratic learning style. This book matches my preferences quite well. It isn't one of these big glossy monsters full of biographical notes about mathematicians and pictures of waterfalls, and it isn't a papa Rudin where you spend nine hours poring over a single page. Some of the rigor that I would have liked in the main text is relegated to appendices, but it's all there, so that's OK. The book shows some signs of its origin as a sequence of lecture notes, but that's not a real problem.