While studying for and becoming a Certified Professional Scrum Master through scrum.org, I did a lot of writing - here's some notes!
TLDR
Scrum is a "framework" with a few parts
Scrum is intended to help teams and organizations create value incrementally in a complex environment.
I personally don't feel like I have enough experience with other "frameworks" to really support how the scrum guide refers to scrum as a "lightweight" framework. I know that there are a few concrete details with lots of room to embody the theories & values underneath the events, artifacts, and team structure. Transparency, Inspection, Adaptation, Respect, Courage, Empiricism, Lean Thinking... these things are so much more than Scrum, but without those things the implementation of Scrum can leave a room feeling deflated, powerless, annoyed, overburdened, and disinterested.
Empiricism, Lean Thinking, Transparency, Inpsection and Adaptation keep Scrum honest
Commitment, Respect, Courage, Opennes and Focus
The 3 roles - Scrum Master, Product Owner, and Developers
The Sprint, Sprint Planning, Sprint Review, Sprint Retrospective and Daily Scrum
The Product Backlog, Sprint Backlog, Increment, and Definition of Done
An overview of the elements that are part of scrum
The tool that can transform ideas into releasable content
Ways to keep the values alive