Which should be the languages to be the master in web development?

Answer 1

You might wanna try HTML, CSS and JavaScript for front end.
On back end you might want Ruby, PHP or Python. :)

Answer 2

It's a combination out of html for the basis, JavaScript to make cool functionalities and CSS to get the whole thing to a nice style. Then there is PHP for the servers processing data and SQL for storing data, but you can create cool webpages without those two. So your ranking should maybe be:
html
CSS
JS

PHP
SQL