DigiDoc was created and is developed and maintained by RIA[1] (Riigi Infosüsteemi Amet, Information System Authority of Estonia).

The format is used to legally sign and optionally encrypt file(s) like text documents as part of electronic transactions.

All operations are done using a national id-card, a hardware token, that has a chip with digital PKI certificates to verify a person's signature mathematically.

After verifying the user's PIN, id-card signs the hash internally and returns a signature which is then stored into DigiDoc container.

The most widely used application is the qDigiDoc graphical desktop software that runs on Microsoft Windows, Apple Mac OSX and on various Linux distributions.