Why did he give me the "bro handshake"? Seriously, what does this mean?

Anonymous
So I've gotten several signs this guy might like me, including giving me his undivided attention when we're hanging out, touches me on the shoulder blade seemingly a lot (like, a quick gentle rub), walking me further than he says he wI'll before we part ways, asking for my number, and asking me to hang out, standing a little too close, etc... but when we say goodbye, he gives me the "bro shake". Why would he do this? He's in his 30s, if that matters...
Why did he give me the "bro handshake"? Seriously, what does this mean?
3 Opinion