Agile is a blanket term for many approaches. The Agile Practice Guide, 2017 describes agile and the Kanban Method as descendants of lean thinking.
Kanban
Kanban is a system for scheduling inventory control and replenishment in lean manufacturing. Refer to Lean and Kanban Method for details.
Agile Frameworks
There are many popular agile frameworks. Refer to the Agile Practice Guide, 2017, Annexure A3 for a detailed explanation of these frameworks.
For the PMP exam, you need to be familiar with Scrum and some practices of Extreme Programming (XP). We have covered these in detail in separate articles.
Scrum
A single-team process framework used to manage product development; refer to Scrum for details.
Extreme Programming (XP)
A software development method based on frequent cycles; refer to Extreme Programming (XP) for details.
Crystal
A family of methodologies that provide for tailoring of agile methods based on project size and criticality; refer to Crystal Methods for details.
ScrumBan
A hybrid of Scrum and Kanban.
FDD
FDD stands for Feature-Driven Development. It is a framework to meet the specific needs of large software development projects.
DSDM
DSDM stands for Dynamic Systems Development Method. It is a constraint-driven framework where time and cost are fixed, but scope is variable.
Scrum of Scrums
A technique for coordinating work of two or more Scrum teams.
SAFe®
(SAFe®) stands for Scaled Agile Framework. It is a knowledge base of patterns for scaling development work across all levels of the enterprise. Refer to Scaled Agile Framework for details.