The picture above truly helps define the difference between Scrum and Agile. The terms are used interchangeably in the industry. Let's try to demystify this.
Scrum is a realistic project management framework for your projects for getting work done. Agile on the other hand is a set of values and principles. To implement agile you need overall alignment across the organization. It requires a significant culture change.
Scrum fosters a self-organizing, cross-functional team that can help teams thinking in an agile way whereas to adopt agile methodology in your team, leadership plays an important role by defining lots of up-front development processes.
Scrum is more focused on innovation. You can experiment with execution. It's focused on delivering business value in the shortest time. In short, Scrum is more flexible. It can react to change quickly as compared to agile's rigid approach.
Scrum collaboration happens every day in form of daily stand-up meetings whereas agile requires alignment with cross-functional teams often in person.
Self-organization and Iterative Development are the most important pillars for Scrum.