Describe the sequence of program execution.

The sequence of program execution in Java can be described as follows:

1. Class Loading: The JVM loads the class bytecode from the file system or network.
2. Class Verification: The bytecode's correctness and security are checked.
3. Preparation: Memory is allocated for static variables and default values are assigned.
4. Initialization: Static initialization blocks and assignments are executed.
5. Object Creation: Memory for the object is allocated when calling new, and the constructor is invoked.
6. Execution of main method: The JVM starts executing the program from the main method.
7. Interpretation or JIT Compilation: Bytecode is either interpreted or compiled into native code for performance enhancement.
8. Memory Management: The garbage collector automatically frees unused memory.

Thus, the program goes through stages of loading, preparation, initialization, and execution, managed by the JVM, which ensures portability and security.