JavaScript is the number one programming language in the world and the most prevalent language in web development. About 97% of all websites in the world were built with JavaScript. That means that there are over 1.5 billion websites being powered by JavaScript.
React Native is essentially the JavaScript React framework for native applications. React Native can be used for cross-platform development. It enables front end developers to build native applications (apps) for Android and iOS using React – a JavaScript library.
React Native is written in JavaScript but rendered in the native platform’s user interface (UI) so you can easily write your app in a language you know but use the same native platform APIs that other apps use.
ReactJS, usually just called React, is a JavaScript library for building user interfaces. React was developed to build the front end of a website. It is the most popular framework of its kind.
React can be combined with other libraries to create entire applications for the web, mobile devices, or Windows desktop. It’s owned and maintained by Facebook but it remains open-source and free.