JavaScript is a dynamically interpreted scripting language which is used for creating and updating web pages. It was originally created by the team at Netscape that was included with the Netscape Navigator Browser. Microsoft made their own version of JavaScript which they called JScript in 1996.
After many years of browsers interpreting JavaScript differently, the Ecma International group decided to come up with a set of standards for the JavaScript language which they called ECMAScript. JavaScript and ECMAScript are one in the same. Each version of the ECMAScript extends JavaScript's functionality further and further.
In the video above, I'm explaining the best way to learn JavaScript.