O canada

Like hey, your door is open or turn on your lights

Or just keep the regular honk and add a very agressive one

my friend's chevy volt has a little horn and a regular horn, the little horn is for people who can't hear your car

Like mine with its main horn and then aftermarket air horns.

Yea my parents tried honking at a friend since they saw them crossing the street and he got mad cause he thought we were trying to tell him to hurry up before he realized we were just trying to get his attention

This guy actually did it
https://www.youtube.com/watch?v=lv8wqnk_TsA

My little car has a little "meep, meep" horn and I wish I had a second more aggressive horn.

there is one... the bedalabuhbuh, bedalabuhbuh, bledahbledahbleh one

I wish there was a way to send friendly messages like 'sorry i didn't mean to' or 'i can't move forward because there's someone blocking the way'.. They might be a bit long

That's generally what two short honks mean.