JavaScript is the easiest language to start learning. It does not need any software to run. A modern browser and notepad are enough to start coding in JavaScript. JavaScript has some of the best online learning materials.
Websites such as Codecademy (https://www.codecademy.com), Code School (https://www.codeschool.com), CodePen (http://codepen.io), JS Bin (https://jsbin.com), and JSFiddle (https://jsfiddle.net) will help you learn JavaScript in short time.
JavaScript is the only language that runs in almost every browser; even in smartphone browsers. As the web is everywhere, JavaScript is also everywhere.