Issues related to the official documents necessary to operate a motor vehicle.
In most of the world, permission to operate a car, motorcycle, truck/lorry, or other motorized vehicle must be granted by the government. The document certifying this permission is known variously as a driving licence, driver's license, driving permit, or other terms in different locales. It both identifies the driver and the classes of motor vehicles he or she is allowed to operate.
In some countries, the driver's license is also the de facto form of official identification, notably in australia, canada, new-zealand, and the usa. The same agencies which issue the driver's permit in those countries usually provide an identity-only card for non-drivers. Furthermore, under the Western Hemispheric Travel Initiative (WHTI), the so-called Enhanced Driver's License issued by some states and provinces can be used in lieu of a passport for travel between Canada and the United States. Questions about this use of government-issued ID should be tagged with identity-cards, as they are more about identity and less about driving.
Questions about obtaining a license are broadly out of scope for this site, as that usually suggests at least semi-permanent relocation, rather than business or leisure tourism; they may be appropriate to our sister site, Expatriates Stack Exchange. Questions with this tag usually cover questions about whether carrying a license from one jurisdiction is sufficient to operate a vehicle in another jurisidction temporarily, or about obtaining local driving permits for a short stay, or about international driving documents.
International driving documents
International driving licenses are not actually licenses, but documents which provide translations of the original license so that local authorities can verify the information. The permit must always be accompanied by the original document, and does not confer any rights or privileges on its own. Additionally, possession of such a permit does not exempt the driver from any local or national laws or regulations.
Whether or not an international permit is required varies by locale. Often, the original document is technically sufficient, but the onus is on the driver to translate it into the local language— and an international permit will be far more likely to be accepted than a personal one.
While not every country requires an international permit from foreign drivers, they may recommend it. Inversely, some countries may not recognize the IDP, but may recognize foreign licenses under other diplomatic or legal arrangements. Furthermore, even if a government does not require it, an agency may require it for car-rentals.
International Driving Permit
Who issues the IDP, and who it may be issued to, varies by jurisdiction. As there are many scams involved with IDPs, it is best to consult with your national auto club or road authority for official information. Generally, the IDP must be issued from the same country where the original license was issued.
Inter-American Driving Permit
In most of the Western Hemisphere, the Inter-American Driving Permit, or IADP, is an alternative to the IDP. Uruguay recognizes only the IADP, and not the IDP.
The stipulations about the IDP generally apply to the IADP as well. Among major tourist destinations in the Americas, the IADP is not recognized in the bahamas, barbados, belize, canada, cuba, jamaica, panama, or in any European possession.