Learning React, 3rd Edition

Chapter 1. JavaScript for React

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Since its release in 1995, JavaScript has gone through many changes. At first, we used JavaScript to add interactive elements to web pages: button clicks, hover states, form validation, etc.. Later, JavaScript got more robust with DHTML and AJAX. Today, with Node.js, JavaScript has become a real software language that’s used to build full-stack applications. JavaScript is everywhere.

JavaScript’s evolution has been guided by a group of individuals from companies that use JavaScript, browser vendors, and community leaders. The committee in charge of shepherding the changes to JavaScript over the years is the European Computer Manufacturers Association (ECMA). Changes to the language are community-driven, originating from proposals written by community members. Anyone can submit a proposal to the ECMA committee. The responsibility of the ECMA committee is to manage and prioritize these proposals to decide what’s included in each spec.

The first release of ECMAScript ...