What computer Language (ex. CSS, HTML, PHP, Java) was used to develop Facebook's Photo-Tagging Features?

[Max K]

I have decent knowledge of Web Programming (HTML, CSS, and learning PHP), but was trying to understand how this feature was developed.

[Daniel]

Its combination of PHP and HTML im not familiar with the fade effect

[Doug Gunnoe]

javascript client side, PHP server side.

http://developers.facebook.com/

http://www.google.com/search?q=ajax

[ǝpoɔ ןןǝɥs]

javascript was used to allow the user (you) to select the face and ajax (javascript + php) was used to search the name of the person you just selected then more php was used to submit a query to one of their databases as that person tagged in that specific photo at this location (x,y coordinates)

its a lot of code but pretty straight forward if you know a ton of javascript/ajax

[mastermaniac]

JavaScript to get the exact coordinates of the tag in the photo: x1, y1, x2, y2
And, I guess HTML's <img> and <area> tags to display them on the browser.
PHP to store the cords, name and other details in the database.
AJAX to send the data to the PHP.

:-)