AJAX and the Web 2.0 hype around 2005 are responsible for the success of the last few years. There were also YUI, prototype.js, ExtJS before anyone used JQuery. But thanks to the popularity of JQuery around 2010 we got at least two JS functions in HTML5 browsers. And the browsers got more compatible with the HTML spec. Before you had to write for IE, Firefox and Webkit with fallbacks for various bugs. Since around 2013 vanilla Javascript is enough, and JQuery popularity is declining. There are React/Angular/Ember/etc nowadays but hopefully soon ShadowDOM will be supported by most HTML5 browsers.