Voseo

Voseo (Spanish pronunciation: [boˈse.o]) is the use of vos as a second person singular pronoun, including its conjugational verb forms in many dialects of Spanish. In dialects that have it, it is used either instead of tú, or alongside it. Use of "tú" is known as "tuteo".

Vos is used extensively as the primary form of the second person singular in Rioplatense Spanish (Argentina and Uruguay), Eastern Bolivia, and Paraguayan Spanish.

The Central American Spanish (El Salvador, Guatemala, Honduras, Nicaragua, Costa Rica, southern parts of Chiapas in Mexico) also exhibits an extensive use of vos, though in Northern Central America the media use tú more frequently. In Nicaragua and Costa Rica, tú is used less frequently.

Vos had not been traditionally used in formal writing except in Argentina, Paraguay and Uruguay. This gradually changed in Central America, where even the most prestigious media networks and press began to use the pronoun vos, reflecting the informal address in Spanish as opposed to the formal address of usted. Nowadays it is very common to see billboards and other advertising media using voseo. In the dialect of Argentina, Paraguay and Uruguay (known as 'Rioplatense Spanish'), vos is also the standard form for use in television media.

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