After learning HTML & CSS what programming language I should learn to become a front-end developer ?

javascript

JS

javascript

JavaScript and then other frameworks like bootstrap, jQuery, Angular js, React etc

First of all html and css are not programming languages.HTML is a markup language and CSS is a style sheet language. A logical pathway for learning will be like this- 1. HTML and CSS 2. JavaScript 3. jQuery 4. PHP and MySQL 5. Python(Great for creating web applications) 6.and then Ruby ...>>>then a long way to go. Which i currently don't know about.