Gender
There are more than two genders. Get over it.
Don't say that only two exist just because you're either too dumb or not willing to understand. Go mind your own business or get informed. Please.

Gender is either binary or nonbinary.

Female and male are gender binary.
Agender, gender neutral and others are nonbinary.

It's not that complicated to understand.
Nonbinary people are using different pronouns, for example they or ze.
Random person: Is he or she a boy or a girl?
Person 2: They are gender neutral. Not a boy or a girl, you should use the pronoun they.