If you are a open source software developer or a content writer you can use Zanata to translate your software strings, User interface text/String, software documentation and localized into any languages.
Zanata is an open-source translation manager that enables a community of translators to work on localising software and documentation using nothing more than a web browser.
Zanata is a project supported by Redhat written using Java and uses modern web technologies like JBoss, Seam, GWT, Hibernate, and a REST API. It currently supports translation of DocBook/Publican documentation through PO files. Projects can be uploaded to and downloaded from a Zanata server using a Maven plugin or a Python client.
You can Submit your software strings, User Interface Text/String,Software documentation that will be translated to Any Language @ translate.zanata.org
Watch Video tutorial: How to get a Zanata account and How to request a Project on Zanata