Google GeoChart API allows to world map with target countries. And with using ISO 3166-1 alpha-2 codes, target countries can be added to the map. These codes show how to add countries and they contains all available countries as list. There are 2 html files, one of them contains countries as English names, other one contain ISO1366-1 Alpha2 codes. By the way, mixed usage is also allowed. This means that in same file both English country names and ISO1366-1 Alpha2 codes. The third file also show this usage.
Note: To get API key, please visit: https://developers.google.com/maps/documentation/javascript/get-api-key