and stuff

What does ‘and stuff’ mean?

I’ve seen this phrase frequently used.

In Calligraphy 

Jeff:  Calligraphy.

Lily:  Oh yeah! It was pretty and stuff.

InHarry Potter

Miguel:  Well, I was pretty unfamiliar with the whole Harry Potter thing and the the story is actually pretty neat. I mean the, the, the little kid is a wizard and, um, he goes to a school of wizards and that’s kind of a neat concept, um, but the special effects and stuff were no where near as cool as other big movies these days like The Matrix and stuff.

What does ‘and stuff’ mean?

Thanks.

What about the phrase “Your stuff”?

In the lesson Dinner Etiquette .

Rafael:  Well, you’ve got to know your stuff about cutlery. You’ve got to be polite. 

I know that stuff means things, but it doesn’t make sense when he says “You’ve got to know your things about cutlery.”