Why some language have gender

Why Divide Nouns By Gender?

from https://k-international.com/blog/why-do-languages-have-gender/

Why do gendered languages exist? After all, English does perfectly well without assigning “feminine” and “masculine” characteristics to objects.

Actually, English used to be a gendered language, too. English speakers stopped classifying most nouns by gender during the Middle English period.  

Basically, gender in languages is just one way of breaking up nouns into groups.  It’s an inheritance from our distant past. Researchers believe that Proto-Indo-European had two genders: animate and inanimate. It can also, in some cases, make it easier to use pronouns clearly when you’re talking about multiple objects.

 Example: I saw it.    (In English we don't know what the it is.)

                 Yo lo vi.  (In Spanish we know that the object is either a masculine or feminine.)

                      Yo la vi.