What's the appropriate term when talking to more than one person?

[Tommy Chong]

So what do you call your mates?

It’s usually ‘My esteemed colleagues…’

Which is fine, because this is how my grandmar usually greets me:

 

[goldfinchmule]

Hello Dr Jekyll.

 

[Toffeepot]

Heads

 

[Gwladys St. Glory]

"you [insert expletive or derogatory term here]" if you're a man addressing male friends; easy.