Replaces indirect object in a sentence.

Ejemplo:

Me gustan los gatos. I like cats.

me	nos
te	os
le	les

Placement:

1 verb, 1 place

Put the pronoun in front of the verb.

Me gusta la ensalada. (I like salad.)

2 verbs, 2 places

Pronoun goes in front of conjugated verb or attached to infinitive

El le va a dar un regalo OR El va a darle un regalo. (He is going to give a gift to her)