Indirect object
The indirect object ("objeto indirecto" in Spanish) is an element in the sentence that is affected by the verb in an indirect way, i.e it's the recepient of the action, benefits from it or gets affected in a negative way, depending on the meaning of the verb in each case.
For example:
Le dio un golpe a su hermano.
He hit his brother (lit: he gave a blow to his brother)
Les pagamos el dinero a los empleados.
We paid the money to the employees.
No he echado sal a la comida.
I haven't added any salt to the food.
Generally, the best way to know where the indirect object is in the sentence is by asking "to whom...", "for whom...", and sometimes "on whom...?
See also El objeto directo
