There are also possessive pronouns in English. Possessive means belonging to. "Her computer" could also be written "the computer belonging to her".
Possessive pronouns include "my" and "mine", "your and yours", "his", "her" and "hers", "our" and "ours", "their" and "theirs". Deciding which possessive pronoun to use depends on what grammatical function it plays in the sentence. You could say "that book is hers" or you could say "that is her book". "Her" (like "my", "your", "his", "its", "our" and "their") is a possessive pronoun functioning as an adjective. Which book? Her book. The other forms of possessive pronouns can function as direct or indirect objects: "When I lost my coat, she gave me hers". Here, "hers" is the direct object of the verb "gave". Remember that possessive pronouns do not have an apostrophe, including the word "its" (i.e. "its handle" for "the door's handle").
If you enjoyed our first quiz on pronouns, you'll hopefully enjoy this one too!