What is Their Difference?
'Ours' and 'Theirs' are both what we call possessive pronouns. They are used to refer to something or someone belonging to or associated with us or others.
Ours vs. Theirs
What's Their Main Difference?
'Ours' and 'Theirs' are both plural possessive pronouns. But one of them is used for first-person and the other is used for third-person. Let's see which is which.
'Ours' is the first-person plural possessive pronoun that is used to refer to something or someone belonging or related to us.
Especially in British English and in informal, spoken language, 'ours' can mean 'our home'.
'Theirs' is the third-person plural possessive pronoun which is used to refer to something or someone belonging to or associated with others.
Theirs as Generic Pronoun
We can use 'theirs' instead of 'his or hers' to show that something belongs to a person without mentioning the gender of those people.
Of + Possessive Pronouns
Sometimes, to show belonging you can use the structure of 'of + possessive pronouns'.