The Dalai Lama, of course, is an extremely popular Buddhist and his books are for the layperson, not scholar and are therefore very easy to read.

The Four Noble Truths are, in fact, the first teaching of the Buddha which was done after reaching enlightenment. This was done at Sarnath and the place where this happened can be visited today.

These four truths became the foundation of all later Buddhist teachings in which the Buddha laid out the path to enlightenment in very simple terms.