What is the relationship between JavaScript and Java?

Despite the similarity in names, JavaScript and Java are entirely different programming languages with different architectures, purposes, and histories.

Main differences:

• Type: Java is a compiled, statically typed language. JavaScript is an interpreted, dynamically typed language.
• Runtime environment: Java runs on the JVM (Java Virtual Machine). JavaScript was originally executed in browsers but is now also used on servers (Node.js).
• Paradigm: Java is primarily object-oriented, although it supports other approaches. JavaScript is multi-paradigm (object-oriented, functional, imperative).
• Syntax: Although the syntax of both languages resembles C-like languages, their semantics differ significantly.
• Application areas: Java is widely used for creating enterprise applications, server-side components, mobile applications (Android). JavaScript is the main language for frontend development, and it is also used on the backend and in other areas.

Historically, JavaScript got its name to capitalize on Java's popularity at the time, but this does not imply a deep familial relationship between the languages. JavaScript was developed by Netscape, while Java was developed by Sun Microsystems (now Oracle).

You can compare them to "Car" and "Carpet" - the names are similar, but the entities are completely different.