There are three terms that I would like to introduce here.
First, lets see what Process Group is. The whole Project Management discipline is divided into five broad Process group, they are Project Initiation, Project Planning, Project Execution, Project Monitoring & Control and Project Closing.
You probably, might be aware of them as well.
When a new Project starts, its in the Project Initiation phase, from Initiation, it moves to Planning, than to Execution and Monitoring & Control and finally its closed. Project Execution and Project Monitoring & Control processes go hand in hand.
So when a new project is started i.e., initiated, all processes of Project Initiation Process Group should be applied to the Project. Similarly when the project is being closed, all Processes of Project Closing group should be applied.
Let me give you more specific example, Identify Risks is a Process of Project Planning group. So when the project is in planning phase, you must identify all the Risks of the project.
Next. Lets see what is a Knowledge Area.
As per PMBOK, There are 9 Knowledge areas. For example, Human Resource Management is one of the Knowledge areas. Knowledge area is a set of specific processes required to be performed to meet a project objective. A Knowledge area may have some processes to be done in Project Planning Process Group and some other processes to be done in Project Monitoring & Control Process Group.
For example, if you take Human Resource Management Knowledge area, Develop Human Resource Plan is processes in Project Planning Group and another process Manage Project Team is in Project Execution group.
Lastly there are 42 process areas; we have already come across two such Process areas. Develop Human Resource Plan and Manage Project Team.
If you are totally confused by now. Dont worry. This is the whole exam syllabus and there is one lesson dedicated to each of these topics!
For now, just remember that there are 5 process groups, 9 knowledge areas and 42 project management processes.

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