I'm really surprised this question has not been asked. I would like to know, how do you say "Happy birthday!" in German? I plugged this into Google Translate, and got the following.
Alles Gute zum Geburtstag!
I feel like this translates literally to "all is good for (your) birthday". What is the logic behind this? Is it idiomatic? Are there other more common ways, or more concise ways, of saying "happy birthday"?