Thank you for your interest in assisting!
Wikipedia relies on volunteers who generate and maintain all content as well as creating policies and guidelines to govern the site. It is a collaborative project, with people from all over the world bringing their skills and interests to join in the compilation and dissemination of knowledge to everyone, everywhere, free of charge. The other projects we maintain are also collaborative, crowd-sourced projects that rely on volunteers. Translation is a volunteer-driven activity on our websites, just like content creation.
If you want to translate content from one of our projects to another, a general approach to translation from English Wikipedia to other projects is provided at w:Wikipedia:Translate us. This approach is likely to succeed on most projects with most languages, but it's a good idea to check on whichever project you wish to work to see if there are different local processes. You can reach out to the "help" or community discussion forum on the project where you want to place the translation. These are generally linked from the side of every page. If you can't find it, you can write to infowikimediaorg for more information. Please, in that case, specify the language project where you want to work (for instance, Italian Wiktionary; French Wikipedia).
If you are interested in helping to translate official documents used for management of Wikimedia projects, this work is also done by volunteers. Meta:Babylon is a good place to begin. There is a section there on getting started which includes some important links, and there is also a section on communication that tells you some of the best places to get in touch with other translators, who may be able to give you specifics about the work. We'd recommend reading the tutorial linked from the "getting started" section before beginning, if you choose to pitch in.
Thanks for your interest, and we hope you will decide to join us.
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