What is the difference between languages for Wordpress and WPML- also how to create multilingual sit

Hi,

(1) What is the difference between languages for wordpress and WPML
(2) Does languages for wordpress also provide translations for all the WPMU plugins?
(3) How do I add support for multiple languages for a custom plugin to languages for WOrdpress, ideally as a plugin (that separately updates from the Languages for Wordpress plugin itself).
(4) Suppose a user wants to create a site which has content in 2 languages- English and French (in the same site)-- Can he do that using languages for Wordpress? If not, then can he do it using WPML? Also, how can he clearly create articles in multiple languages- both articles have same content only the languages are different in each article.

Yours sincerely,
Arvind.