This is simply an amazing book. The author, a psychiatrist, survived four concentration camps, and a good part of the book (the book is 160 pages in length) details those experiences and how he survived. The remainder revolves around his theories that we can find meaning from suffering. He quotes Nietzsche that he who has a "why" to live for can bear with almost any "how."
This a good article about the book, http://benjaminmcevoy.com/7-lessons-learned-mans-search-meaning-viktor-e-frankl-book-review/