Popular slang in Germany. Means "Everything is clear" but it used it many different way.
PersonA: Hey! How are you?
PersonB: Alles klar!

PersonA: Did you understand?
PersonB: Alles klar!

PersonA: Are you okay?
PersonB: Alles klar!

etc. etc. It's a very multi purpose phrase. Your tone of voice can change the meaning depending on the situation.
by SugarSlinky August 4, 2008
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