All my family/friends know I earn money on the Internet, but none of them are really savvy enough to understand how exactly etc, so I don't tell them.
Being involved in an activity I love, I don't see any reasons to hide it from my family/friends. If they ask for any advice or help, I am usually responsive and enthusiastic to share what I know. No, I am not afraid they may "steal" anything out of me.
I tell my family and friends and they don't get it. "What's that" they ask. Most of them just think I sit in front of the computer and play around all day. So I don't bother talking about it with them anymore.
Yeah, most people don't understand what I do online, but when I show my friends the check, they always become interested, but never want to put in the time. They generally just forget an hour or so later. All the better for me. My family knows for the most part though.
for me, my nuclear family knows but no one else does. my friends are always curious what i do all day so i just tell them i sell stuff on ebay LOL. it's not like they are not good friends and i don't trust them...but you just never know... they are very computer/street saavy so i have to becareful.