Part of a series by Oxford University Press, this book, 'Buddhism: A Very Short Introduction', follows the same format as other texts in the Very Short Introduction series -- it has fewer than 150 pages, is well indexed, has a useful glossary, accessible and enjoyable narrative, and captures the essence in a very short space the major points of its topic. There are probably nearing 100 volumes in this Very Short Introduction series (making it, ironically, not a Very Short series), but among those that I have read, this text stands out as being one of the best.
Damien Keown, of the University of London and the Royal Asiatic Society, addresses Buddhism past and present, East and West. Beginning with narrative tales the help to exhibit the principles, Keown examines in turn the major questions. First, with regard to Buddhism, is this -- is Buddhism really a religion? Often categorised as such, it is often the exception proving the rule. Many take strong spiritual and philosophical ideas from Buddhism (sometimes without knowing it) but do not subscribe the larger system of practices -- but perhaps most telling, Buddhism is a non-theistic way of being. Keown looks at seven dimensions of religion, and concludes that Buddhism does fit a broader definition of religion.
Keown proceeds from there to look at the origins of Buddhism, the life of the Buddha, ideas of karma and reincarnation, and the central ideas of the Four Noble Truths in Buddhism. From these beginnings, Buddhism branches out, the largest grouping being the Mahayana (who get their own chapter), and other spreading first across Asia and then to the rest of the world.
Like other books in this Very Short series, there are useful maps, a nice snapshot timeline, and suggestions for further reading, should the Very Short introduction not prove sufficient (and for many, this sample will leave the reader wanting more). I cannot speak too highly of this series, and of this volume on Buddhism by Keown in particular.