If I decline a Friend Request, does that person who sent it realize I denied it?

[help???]

I have don't this to face book and many dating services, which just don't give up, even the ones I never paid for, the message comes over; request denied, however; (with the mix of personalties out there these days) and they are getting worse, (every six months, over 500 inmates are released from prisons Just in my own state alone,) In prison many learn "new talents", (overcrowding in prisons, which speaks for itself a thousand words on crime) and alsdo in foreign countries, and it not ALL GOOD! if they get angry they can retaliate by becoming a hackers, which most are qualified for and do anyway..sad but true..fewer and fewer of us are safe out of prison. *(even the men/males are now *more suspicious of their own safety in our society!)