Beyond the exciting and wonderful story it describes, this great work of Herman Hesse is especially careful decription the course of a life, that of a man who seeks happiness and tries to find it in different experiments. Some will bring the happiness and other comfort and pleasure. But in the background, Siddharta is animated in a perfectly universal spiritual quest, and this short novel can speak to us all. It should however be noted that if the story is set in an Indian region at a remote period, Hesse was actually studded with thoughts and references to a theology that is much closer to Christianity. This is hardly surprising, given the author's journey. But the reader should be aware in order not to be misconceptions about Buddhism.
This book reads and can be read at very different ages, and usefully join your library wisdom of other novels like The Little Prince, The Alchemist or Jonathan Livingston Seagull.