What is pink lemonade?  Does it come from pink lemons?  If so, where are they?

It's not regular lemonade with food coloring because it taste different.  It's not strawberry, because there is strawberry lemonade.  It's not raspberry, because it doesn't taste like raspberries.  

Then what the heck is Pink Lemonade? 

If you can give some insight on this, please feel free.  I just love the stuff, but I don't know what I'm drinking.