This is a funny way to put it. It is used everywhere??? Front-end means everywhere?

Front-end means programming the web browser. There’s a lot more to IT than the front-end web. For example:

• back-end web where Node.js plays second fiddle to many other back-end languages like PHP, C#, Java, Ruby, Scala, and so on
• desktop where Electron plays second fiddle to Java, C#, and C++
• mobile where Java, Kotlin, and Swift dominate — React Native is a secondary player here
• data science and machine learning where Python dominates
• IoT where C/C++, Java, Python and others are used much more than JavaScript.
• robotics
• virtual reality
• enterprise business computing like ERP
• etc.