For those of you confused, the parties being described here are ones that you "walk into one but don’t know a single person there...or perhaps you’re only vague

For those of you confused, the parties being described here are ones that you "walk into one but don’t know a single person there...or perhaps you’re only vaguely connected to the host". Though some of the advice given would be helpful even in a BBQ with a large group of your friends.