Agile methodologies are approaches in project management and software development that emphasize agility, flexibility, and close collaboration to achieve better results in rapidly changing environments. They differ from traditional, plan-driven approaches by focusing on iterative, incremental development and continuous adaptation to changing requirements.

Here are some well-known agile methodologies:

1. Scrum: Scrum is one of the most well-known agile methodologies. It focuses on breaking work into time periods called sprints, during which teams work in short cycles to deliver functional product increments regularly.

2. Kanban: Kanban is a visual workflow management system. It emphasizes continuous delivery and flexibility. Tasks are represented on cards and moved through various phases of the workflow.

3. Extreme Programming (XP): XP is a technically-oriented agile approach that aims to improve software development quality through practices like continuous integration, automated testing, and pair programming.

4. Crystal: Crystal comprises a set of agile methods that vary based on project size, priority, and cultural context. It places a strong emphasis on team collaboration and regular reflection.

5. Dynamic Systems Development Method (DSDM): DSDM emphasizes collaboration between business experts and developers to prioritize user needs. It values timely product delivery and adherence to quality standards.

6. Feature-Driven Development (FDD): FDD emphasizes iterative and incremental development of features. It uses a model-based approach and places a strong emphasis on creating clearly defined feature models.

These agile methodologies share the goal of maximizing customer value, empowering teams to leverage continuous feedback, and adapting to changing requirements. The choice of the most suitable agile approach depends on the specific project requirements and team preferences.