Many world languages such as Spanish and German assign grammatical gender to nouns. While Arabic also does this, it takes it one step further and includes a grammatical gender aspect in verbs too. For instance when asking someone how they are, the phrase changes depending on whether the person is male or female:

How are you?

كيفَ حالُكَ؟
(kayfa Haloka)
Addressing to a male

كيفَ حالُكِ؟
(kayfa Haloke)
Addressing to a female

Moreover, the word "you" translates several different ways based on gender-specification. For instance, when addressing a singular male you use the word أنتَ (aanta) and أنتِ (aanti) with a singular female.