Ken Schwaber and Jeff Sutherland developed Scrum; the Scrum Guide is written and provided by them. Together, they stand behind the Scrum Guide. Scrum (n): A framework within which people can address complex adaptive problems, while productively and creatively delivering products of the highest possible value.
Scrum is described as a framework, not a methodology. The Scrum Guide provides just enough prescription to allow Scrum to work and encourages its ‘users’ to be smart, adding practices and other things specific to them on top of the framework as needed to form their process. Scrum is about Value not Work. Reflections from Scrum Guide Update
The rules of Scrum bind together the roles, events, and artifacts, governing the relationships and interaction between them. The rules of Scrum are described throughout the body of this document. Specific tactics for using the Scrum framework vary and are described elsewhere.
The Scrum Guide Reordered 2020 is based on about 95 percent of the text of the Scrum Guide 2020, extending its original structure by adding additional categories, for example, on self-management, commitments, or accountability. The audiobook of the Scrum Guide 2020 is a 22-minute long MP3 file.