Vosotros - This word is only used in Spain. All of Latin America does not use this word. It means "you guys" and is only used in informal situations. Examples would be with your friends, family or anyone else that you are familiar with.
Ustedes - This word is used in both Spain and Latin America. In Spain, the word is only used in formal occasions with your professors, or some that is older than you to show respect. However, in the rest of Latin America it is used as vosotros is used Spain and as ustedes is used in Spain. It also means "you guys."
