All airlines now use electronic paperless tickets (E-ticket), this means that passengers are admitted to check-in for their flight just by presenting only a booking code and a valid photo identification document. Passengers who fail to show an identification document at the check in will not be accepted on board.
In case of international flights, before travelling it is extremely important to check always identity and health documentation required by the destination country: entry into a country may in fact be denied to those travellers who show irregular, incomplete or non-compliant documents.
At the airport, it is compulsory to show a valid photo identity document both at the check in (with the booking code) and at the boarding gate (with the boarding card).
EU national identity cards are usually accepted as valid identification documents for entry into EU countries and into a limited number of non-EU countries mostly in case of group tours organised by Tour Operators.
The passport gives right of entry into any country of the world whose Government is recognised by the issuing country. For some countries it is however compulsory to apply also for a VISA, with costs, conditions and procedures that vary from country to country. Special conditions and procedures apply to travellers to the USA, so that, before travelling, it is important to set up correctly the issue with the local US consulates and embassies.
The driving licence is not recognised as a valid identification document for international travel allowing entrce into a foreign country. For this reason it is preferable not to report to check-ins relying on driving licences only, since they might not be accepted.
For safe and healthy travel, access to some countries might be subject to a number of compulsory vaccinations, while other vaccinations and/or some further prevention measures may be warmly recommended. For information ask your local National Health Institutions for international travel and strictly refer to their guidance and regulations.