Internationalization is a collection of modules to add multilanguage features to Drupal. I've created this module in 2004 for this web site to be multilingual, as I was needing a home page in English and Spanish. Since then it's been downloaded more than 300000 times and it powers more than 65000 sites, being one of the top 50 Drupal modules. I am still the maintainer of the module and I provide consulting and customization services for the module and multilingual sites built using it.