This is a very wide subject
1) I just want to have mutiple languages (character sets) on my page.
Simple answer - user UTF-8 or other unicode to encode your pages
2) I want to have my page display with different language strings
Simple answer - use babelfish to just encode your page
next answer - generate static strings on your site from a language file which has strings in multiple languages. Select the language file nased on user data
3) I want to have a full multilingual site
Simple Answer - this is a very complicated task for a beginner. Try the above first and you will then have more questions that will eventually lead you to the full solution