The official language in Uruguay is Spanish. However, there are a few districts along the Brazilian border where Portuñol might be spoken, which is a mix of (Brazilian) Portuguese and Spanish.
Uruguay’s official currency is the Uruguayan Peso ($) UYU. However, the Brazillian Real BRL (R$), the US Dollar (US$) and even the Argentinian Pesos are likely to be accepted in local businesses and sometimes in taxis too. Always check first since exceptions may occur.
Also watch out for the difference between currency codes, since prices sometimes might be in Uruguayan Pesos ($) or in US Dollar (US$). Here is an example from a local store: