Four Genders of Noun

In English, the four genders of noun are masculine, feminine, common, and neuter. 

Masculine nouns

 refer to words for a male figure or male member of a species (i.e. man, boy, actor, horse, etc.)

Feminine nouns

 refer to female figures or female members of a species (i.e. woman, girl, actress, mare, etc.)

Common nouns

 refer to members of a species and don't specify the gender (i.e. parent, friend, client, student, etc.)

Neuter nouns

 refer to things that have no gender (i.e. rock, table, pencil, etc.)