Why is the source code converted into bytecode before execution?

Java source code is converted into bytecode to ensure portability and security. Bytecode is an intermediate representation, platform-independent, executed by the Java Virtual Machine (JVM).

Advantages of this approach:

• Portability: the same bytecode can be run on any platform with a JVM.
• Security: JVM controls the execution of bytecode, preventing dangerous operations.
• Optimization: JVM can perform dynamic optimization at runtime (JIT compilation).

Thus, converting to bytecode allows programs to be written once and run anywhere JVM is available, without the need for recompilation.