When someone starts following you around on social media by friending the
people that you are already
friends with whom don't know about the disagreement with you and the other person. A good example of this is in the
case of Donald Trump TWEETING that Barack Obama had 'wiretapped' him during the election.
By "wiretapping" - Trump was using an 'expression' that
literally meant:
"he was into my business" or "he was reading my posts"
A good example would be if Trump were
friends with Sheryl Crow on Facebook and then later Obama hits up Sheryl Crow with a friend request which she accepts and then Trump makes a comment on Sheryl's feed like,
"
Hey, I heard that
Lance lost his testicle. I'm sorry to hear that. I guess that he wasn't covered under Obamacare..."
Which Trump thinks is 'somewhat' of a 'private conversation' because Sheryl Crow's posts aren't usually public, but what he doesn't know is that Obama friended her once he found out that Trump and Crow had been 'sharing statuses' and so Obama is categorically "wiretapping".
That's a 'basic' explanation of what Trump meant when he said, "I just found out Obama was wiretapping me."