We are living in the age of algorithms. Information seeking, loan application, finding a route between your home and holiday destination – all activities are mediated by technology that uses a special algorithm. What is an algorithm in simple terms? John MacCormick introduces nine notable algorithms that we use every day.

First of all, this book is not a classic book on algorithms. It won’t teach you algorithmic complexity or Big-O notation. You won’t find any pseudocode or code snippets on its pages. It only teaches you to appreciate algorithms and gives you some hints to start your own journey in the field if you like what you read. This book is popular science at its best! MacCormick selected nine algorithms, or nine groups of algorithms, that drive our everyday life. Search engines have two chapters, one describing how keyword search and indexing work and one devoted to PageRank. Public key cryptography and digital signatures are the two most exciting chapters. We loved working through the examples in these chapters. The chapters on data compression and error-correcting codes are equally good, maybe the examples are a bit drier. The chapter on databases is more about the story behind relational databases the explanations are a bit hard to follow. The pattern recognition chapter tries to cover many topics, from k-nearest neighbors to neural networks. Although it does a good job explaining the basics, the examples are not as detailed as the examples in other chapters. The last chapter on computability is a bit hard to digest at first, but it’s worth reading it twice (or many times) since provides insights into what computer science is about.

We recommend this book for those who love technology and want to get a glimpse into computer science. The reader will get an understanding algorithms and why they are important.