The use of "Jo"

So as you may have noticed, there is now a running slideshow of Prague in my side bar, I am trying to make it bigger, bear with me...

A lot of people say "jo" here (pronounced yo), it's the informal version of yes. I have gotten a few recommendations to use it more often, but I much prefer ano. Something about saying "Yo" makes me feel a little bit like a white-trash rapper... sorry. I will try to say it without giggling, but it's hard...