xhtml and javascript mostly...probably with extra code for specific functions.
to find out a web page's source code right-click page and select "view page source"
php...
To change the language on Facebook, go to the settings menu, then click on "Language and Region." From there, you can select your preferred language from the list provided.
There is a option for change language in down side of facebook page.
The language displayed on the Facebook login page is typically based on the language settings of your web browser or device. You can change the language by locating the language settings within your Facebook account or adjusting the language settings on your browser or device.
To change the language in Facebook messenger, tap on your profile picture in the app, choose "Language," and then select the language you want to use. If you encounter any issues, you can contact Facebook support for assistance.
Your Facebook language settings may have been changed to French accidentally. You can change them back by going to the settings menu, selecting language, and choosing your preferred language.
liyerature review on facebook language
Matuhunn
PHP
scroll to the bottom of the facebook page. the language should be on the left side next to "facebook" Click the language then a box will pop up. Click English.
Leet speak!
because many people in the world are cannot say english...thats why google have different language.
in and on facebook