further to a passport, one of the most important documents for anyone residing in brazil, or hoping to conduct any sort of business in brazil, or even for visitors staying for a long-term vacation, is a cadastro de pessoa física - cpf.

a cpf number translated literally means 'registration of a physical person', and is brazil's way of keeping everyone's information in a central database. 

the equivalent of a cpf, but for companies, is the cadastro nacional da pessoa jurídica - cnpj, or national registration of legal entities.