Demonstrative pronouns are used to point out the persons or things for which they stand. English has just five of them and they are: this, that, these, those and such.
This is the prize I got.
That is her house.
These are the girls who won the prizes.
Those are the pictures to be framed.
I may have offended you, but such was not my intention.
Note that the words this, that, these, those and such can also be used as demonstrative adjectives. Demonstrative adjectives are followed by the nouns or pronouns they qualify.
This tree is taller than that tree.
Those houses look imposing.
Nobody likes such people.
Demonstrative pronouns only stand for certain nouns, and they are not immediately followed by the nouns.
This is my daughter.
These are the only apples left.