Spanish demonstrative adjective
A demonstrative adjective identifies a particular noun among a larger group.
The English demonstrative adjectives are this, that, these and those, and the Spanish demonstrative adjectives are este, ese, aquel and their femenine and plural forms.
As they are going to modify the nouns they are refering to, they need to agree in number and gender with them.
Me encanta esta película
I love this film.
Esos zapatos son bonitos.
These shoes are pretty.
Aquellas niñas juegan al escondite.
Those girls are playing hide and seek.