What web languages are needed to be learnt for total client-side web programming?

Answer 1

-JavaScript (primarily)
-HTML*
-CSS*
-Any language running on a client device that interacts with a remote service is a client-side language.
Note:,HTML and CSS aren't really "programming languages" per-se. They are markup syntax by which the Client renders the page for the User.

Answer 2

html
CSS
JavaScript