What is "certified"

The certificate, digital certificate, is a computer file that contains a set of information relating to the entity for which the certificate was issued (be it a company, natural person or computer) plus the public key for the private key believed to be held solely by the entity specified in the certificate.

To Provisional Measure No 2.200-2 of 24 August 2001 sets out the rules for the creation of the ICP-Brasil and the associated DPC as well as the use of digital certificates in Brazil, legal aspects and aspects necessary for an entity to become an Intermediate CA and thus issue digital certificates to other entities guaranteeing authenticity, integrity, non-repudiation and legal validity of electronic procedures by these entities.

To Law 11.419 of 19 December 2006 bases the electronic judicial proceedings in Brazil. In it, there is article 20 of chapter 4, which changes article 38 of Code of Civil Procedure (Law 5,869 of 11 January 1973) so that authentication by digital certificates is also legally valid.

Fragment taken from: http://en.wikipedia.org/wiki/Public_key_certificate