The following document describes the approach taken for handling internationalisation and localisation in the Debian project describing the infrastructure, and tools available for translators and package maintainers as well as the work done by the different translation team members.
English is often regarded as the official language of most free software projects. This assumption affects users of free software and users of information systems generally, to the degree that "They should all just speak English!" is a frequent reaction to internationalisation projects. On behalf of the majority of the world's population - who do not speak English - a great deal of work is done voluntarily in the Debian project, to ensure that program interfaces do not only present their messages in English and that most documentation is not only written in English.
Currently, most of the working groups within Debian use English as their main language for information exchange (discussions, documentation, etc.). Developers, even if not native speakers, program code with an English interface and write documentation in English. The main information sources of official documentation (including the project website) are first written in English.
A single working language helps coordinate work of multiple developers worldwide, and helps people exchange their ideas. Englis is the common language for communication with Debian developers. However, using only English disadvantages many potential users and limits the pool of potential developers. It's an accessibility issue, as well as a usability issue. We want everyone to be able to use their computer effectively, regardless of the languages they are familiar with or can understand, and that's what internationalisation is about.