What happens when you compile and run a Java application?

Explains the path from Java source to bytecode and running code, including class loading and the JIT without turning the answer into JVM trivia.

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TL;DR

The Java compiler, usually javac, compiles .java source files into JVM bytecode stored in .class files. At runtime, the JVM loads the required classes, verifies and links them, initializes their static state, and executes their bytecode. The JVM can begin by interpreting code and compile frequently executed paths into native machine code with a just-in-time compiler. The JDK is the development kit that includes the compiler and runtime tools; the JVM is the engine that executes bytecode.

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Core answer
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Overview
This question checks whether the candidate can describe Java's execution model clearly without confusing the JDK, JVM, bytecode, and machine code.
The Java compiler, usually javac, compiles .java source files into JVM bytecode stored in .class files. At runtime, the JVM loads the required classes, verifies and links them, initializes their static state, and executes their bytecode. The JVM can begin by interpreting code and compile frequently executed paths into native machine code with a just-in-time compiler. The JDK is the development kit that includes the compiler and runtime tools; the JVM is the engine that executes bytecode.
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Saying Java source is interpreted directly.
Treating the JDK, JRE, and JVM as interchangeable names.
Claiming Java is platform-independent without mentioning the platform-specific JVM.
Assuming all bytecode becomes native code before the application starts.

What happens when you compile and run a Java application?

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