If trying to pass the PMP Exam, or also if just generally following the PMI Methodology, you will know that main framework has 5 Process Groups and 10 Knowledge Areas.  This is a foundational platform from which all project and business management can follow (no matter what industry, all departments and all sizes of projects ($1,000 to $100 million).

The beautiful thing about these Process Groups is that they explain how to "flow" through a project or business event (Initiate, Plan, Execute, Close and continual Monitoring and Controlling throughout) similar to phases or stages.  And then while flowing through the project, you have Knowledge Areas that are similar to having sub-plans within the project, which include: Scope, Time, Cost, Quality, HR, Communications, Risks, Integration, Procurement, Stakeholders.

However, to take things one more step into the details, each Knowledge area in turn is broken down into Inputs, Tools and Techniques, and Outputs.  Often the Inputs and Outputs do not get a lot of recognition, the focus is usually the tools and techniques.  It can be noted that they also have much overlap with tools that have been around for decades and come from the TQM movement - from guys like Demming, Juran, Crosby, Taguchi, etc.
The three parts can be defined as;
  • Inputs - items that will be acted on
  • Tools and techniques - mechanisms applied to the inputs to create the outputs
  • Outputs - items that are a result of the process
If you are writing the PMP exam, you should know the inputs/output in addition to the tools and techniques. For detailed lists/matrix/presentations, check out the links below:

Presentation - Amit Gupta
Presentations - University of Luton

Matrix - Proplan

visual of the iPhone app

NOTE:  there are also apps on the iPhone or Android that help you memorize the inputs and outputs, just conduct a search for PMI and you will be find several tools to support your studies.
Good Luck :)