Quark
Der Beste
Because German has a gender for everything - unlike english. So they have 3 ways to say 'the' and due to this also a bunch to say everythign else related to the word. I never figured out why all windows are female, all cars are neutral and all dogs are male (I think). Just seems unnessesarily complicated to me. French and other latin based languages are the same but only male/female.
It's also 'cause the article indicates the place of the word in the sentence. If it's a subject, dative, accusative or genetive.
Voilà.