The only way to address two or more
people.
Y'all sounds a heck of a lot better than youse guys and is more efficient as well. Only say it if you're from the south unless you want to get laughed at because yankees
don'
t know how to pronounce it right. Ya'll is spelled incorrectly and "all y'all" is perfectly legitimate. Never use y'all to refer to one person--it makes things really confusing.