This book contains about 250 exercises that are an integral part of the text. Eachpart contains its own collection of exercises with own numeration. They are not onlyan integral part of the book, but also indispensable for the understanding of all parts whose collection is the content of this book. It can be expected that a careful readerwill complete all these exercises.This book is intended for graduate level students majoring in pure and appliedmathematics but even an advanced researcher can find here very useful informationwhich previously could only be detected in scientific articles or monographs.Each part of the book begins with its own introduction which contains the facts(mostly) from functional analysis used thereinafter. Some of them are proved while the others are not.