According to the definition by Ken Schwaber and Jeff Sutherland, the creators of Scrum, “Scrum is a framework within which people can address complex adaptive problems, while productively and creatively delivering products of the highest possible value” and it is one of the most popular methodologies today for software development.

Although popular in the software domain, the concept of Scrum, interestingly enough, was initially proposed as a general project development framework in a 1986 paper by Hirotaka Takeuchi and Ikujiro Nonaka in the Harvard Business Review.

Ken Schwaber and Jeff Sutherland keep updating their Scrum Guide at the Scrum.org website. This Guide is the mandatory source for starting to use Scrum.

When looking for a practical approach, “Scrum from the Trenches” by Henrik Kniberg, is a very good hands-on introduction on how to use Scrum. You can buy the book (at Lulu.com or at Amazon) or you can download a free copy at InfoQ.

Still in the “hands-on approach”, “Kanban and Scrum - Making the Most of Both” is another book by Mattias Skarin and Henrik Kniberg, that explains how to apply Kanban and Scrum methodologies to your project. The book can be downloaded for free at InfoQ.com or you can buy a printed version from Lulu.com.