What is the impact of disabeling the enforce clean and canonical URLs option?

Problem/Motivation

When people go to my homepage the page is forced to go to the canonical URL.
So it doens't show the clean version: domain.com
But the domain with path: domain.com/home

When I disable the Enforce clean and canonical URLs option I get the clean homepage presented URL without the /path.
This is exactly what I want but I can't estimate what impact this has on the rest of my site and pages?

Question

• What is this function doing?
• What is the problem when I don't enable this functionality?
• Are my redirects still working?