cPanel is a server management program used to help website owners easily be able to manage normally complex website services. In fact cPanel has made running a website so easy almost anyone can do it with no prior experience.
WHM is the server administrator part of cPanel and requires more skills to run. cPanel is the individual website control panel and is very easy to use.
- You can't have WHM without cPanel.
- You can have cPanel without the WHM.
For the complete understanding of cPanel and how to get started using it please go here: Understanding cPanel