Scrum

The “Scrum Guide” at http://www.scrumguides.org is a good resource to understand Scrum.

What is Scrum?

Their definition of Scrum from the “Scrum Guide” is:

A framework within which people can address complex adaptive problems, while productively and creatively delivering products of the highest possible value.

And they add that Scrum is:

Lightweight
Simple to understand
Difficult to master

Scrum Roles

Scrum Team
Product Owner
Scrum Master

Scrum Meetings (“Ceremonies”)

Scrum (“standup”)
Sprint Review
Sprint Retrospective (“retro”)