According to the blurb on the book's back cover, "This book offers a highly accessible introduction to natural language processing, the field that supports a variety of language technologies, from predictive text and email filtering to automatic summarization and translation". Putting it all together, this book teaches the reader how to do something highly specific and practical with the Python programming language. I put it this way because there are many books out there that will teach you how to learn Python, or some other programming language, which includes learning various typical tasks, but they don't teach you where to go next.