Well .... those two words actually mean a whole range of
things
When two people come together they've got to communicate how they
want their relationship to be. Alot of matters need to be agreed
upon. That's what I call setting boundaries.
One does not automatically know exactly how to behave in a
relationship - thus boundaries must be set.
E.g. Work vs couple time. Is he a workaholic? How much phone time a
day is enough?
E.g. A cosuming hobby, like gaming 
Are you
being ignored? Or are you denying him space?
E.g. Closeness to other people. Where do you draw the line between
harmless friends and flirtation?
To set boundaries couples should try to do it 1. fairly, a
reasonable compromise that you both can live with, and 2. honestly-
lay your cards on the table. No "testing him" nonsense, no "I
expect him to read my mind" games.
When you have good boundaries in place, and you both know clearly
what is OK and what is not, I think the guy (and yourself) are
happier because he knows where he stands, he gives you respect cos
he knows you don't take just any nonsense, and he acknowledges that
you've made some sacrifices to keep him happy too, and overall the
relationship is healthy & reaches a deeper understanding
through the process of working to achieve a compromise.
