What are the main elements of the agreed EU Digital COVID Certificate?

The EU Digital COVID Certificate system covers three different types of COVID-19 certificates: a vaccination certificate, a test certificate, and a certificate of recovery.
The EU Certificate can be issued and used in all EU Member States to facilitate free movement during the COVID-19 pandemic. All EU citizens and their family members, as well as non-EU nationals legally staying or residing in the Member States and who have the right to travel to other Member States, would be eligible to receive such certificates free of charge.