This book is accessible, aimed at a general audience. But it is also aimed at those programmers and scientific researchers, people with experience of conventional computers who wish to gain knowledge and experience of quantum computing but do not wish to trawl through the extensive and complex literature. This book will explain the programming techniques which will likely be needed to write a quantum computing program to solve their particular problems.The subject of quantum computing is receiving a lot of publicity at the moment, with many stories in the press about how it is going to revolutionise our lives, or break the world's encryption systems. However, most of these stories seem very short on hard facts about how quantum computing actually works. In fact, there seems to be a general lack of easy-to-understand technical information about quantum computing. Whereas there is plenty of complex technical material available.This book is going to attempt to fill the gap. It will attempt to simplify the subject, clarifying the essential concepts, while still retaining sufficient technical depth.