How does returning and parameters work?

So, recently I've been interested in scripting. But the thing that really stunts my learning is trying to wrap my head around when these would be used, why they're used, and how they're used. I've gone around the web, even the official form I believe. I just can't grasp how they work. Is there an explanation that could be more simple for me to understand? Or am I just overthinking it?

If you haven't already, try this: Functions and click the Returning Values section on the right. Returning values essentially gives a function an outputted value that you can use as a regular variable if you call return (value) at the end of a function, and parameters are the things inside of parentheses in a function like Part.Touched:Connect(function(parameter)