Ok I am confused

10:21 am Reference

I have been hearing about patent term extension availability but I don’t know under what conditions the extension is possible. I have heard the it the patent process is delayed beyond the 3 year maximum time period an extension might be possible to guarantee the patent holder will be able to have a full 20 years of protection. I know this is a complex issue and many conditions must be met before the patent term extension will even be considered. If someone out there can break this down to me in pretty simple terms I would really appreciate it. I think alot of people would!