“Both formerly and now, it is only suffering that I describe, and the cessation of suffering.”
– Siddhārtha Gautama
The Teaching of Buddha is a collection of writings on the essence of Buddhism, selected and edited from the vast Buddhist canon, presented in a concise, easy-to-read, and nonsectarian format. It also includes a brief history of Buddhism, a listing of the source texts, a glossary of Sanskrit terms, and an index.
You can get this book for FREE from Bukkyō Dendō Kyōkai America, the Society for the Promotion of Buddhism. I prefer to read this book as a philosophy of life, a different perspective on things, rather than a religious dogma. There are some great lessons to be found within this book and within yourself while reading it. Siddhārtha Gautama tackles some tough philosophical questions, of which Western philosophers have been dealing with for centuries, from a unique perspective. I would suggest reading On Buddhism by Keiji Nishitani (PDF) as a companion to this book.
Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it.
The Teaching of Buddha (PDF)