This is Vol. 1 of Bioinformatics Algorithms: an Active Learning Approach, one of the first textbooks to emerge from the recent Massive Open Online Course MOOC revolution. A light hearted and analogy filled companion to the author’s acclaimed Bioinformatics Specialization on Coursera, this book presents students with a dynamic approach to learning bioinformatics. It strikes a unique balance between practical challenges in modern biology and fundamental algorithmic ideas, thus capturing the interest of students of both biology and computer science. Each chapter begins with a biological question, such as Are There Fragile Regions in the Human Genome or Which DNA Patterns Play the Role of Molecular Clocks and then steadily develops the algorithmic sophistication required to answer this question. Hundreds of exercises are incorporated directly into the text as soon as they are needed; readers can test their knowledge through automated coding challenges on the Rosalind Bioinformatics Textbook Track.