The process of making an application ready for global usage is globalization, or G11N (for the 11 letters between the "g" and the "n" in globalization). Globalization consists of two steps: internationalization, or I18N (for the 18 letters between the "i" and "n" in internationalization), and localization or L10N (for the 10 letters between "l" and "n" in localization—if you're sensing a pattern here, yes there is, people working in this field are particularly fond of numeronyms). The atomic units for globalization are locales. Locales are the most important piece of G11N.
Locales are languages and calendars; date, number, and currency formatting; spelling; writing system direction; etc., that are specific to a geographic region. For instance, the English (color) and date formats (month/day/year) used in Brooklyn are not exactly the same as the English (colour) and date formats (day/month/year) used in Perth.