Difference between Compiled and Interpreted Language
Tags: programming, java, cpp
Published: 2024-02-26 13:23:02


Compiled and interpreted languages are two different approaches to executing code:

## Compiled Language:

- In a compiled language, the source code is translated entirely into machine code (binary) before execution. 
- This translation process is done by a compiler, which converts the entire source code into an executable file or another form of machine code.
- The resulting compiled code is usually specific to the target platform (such as a particular operating system and processor architecture).
- Examples of compiled languages include C, C++, Rust, and Go.




## Interpreted language

- In an interpreted language, the source code is executed line-by-line or statement-by-statement without the need for a separate compilation step.
- Instead of compiling the entire source code into machine code beforehand, an interpreter reads each line of the source code and executes it directly.
- This allows for more dynamic behavior as code can be modified and executed on-the-fly.
- Interpreted languages are often platform-independent since the interpreter itself abstracts away the underlying hardware.
- Examples of interpreted languages include Python, JavaScript, Ruby, and PHP.











Here are some key differences between the two:

- **Execution Speed:** Compiled languages generally execute faster because the entire code is translated into machine code upfront. Interpreted languages may have a slight overhead as each line of code is translated and executed sequentially.
- **Portability:** Interpreted languages are usually more portable because they can run on any platform with the appropriate interpreter. Compiled languages often require recompilation for different platforms.
- **Debugging**: Debugging compiled languages can sometimes be more challenging because the source code isn't directly executed. In interpreted languages, debugging can be more straightforward as you can inspect the code during runtime.
- **Development Cycle:** Compiled languages typically have a longer development cycle due to the compilation step. Interpreted languages offer a shorter development cycle since there's no separate compilation step required.


Both approaches have their advantages and are suited to different tasks and preferences. Some languages, like Java, utilize a combination of both compilation and interpretation through the use of bytecode and a virtual machine


**Note:-**
Java is often described as a "compiled" language, but it's more accurate to say that Java uses a combination of compilation and interpretation.
Here's how it works:

1.Compilation to Bytecode:

- Java source code is first compiled into an intermediate form called bytecode. This compilation step is done by the Java compiler (javac), which translates the human-readable Java source code into platform-independent bytecode instructions.
- Bytecode is not machine code; instead, it's a set of instructions for the Java Virtual Machine (JVM) to execute.

2.Interpretation by the Java Virtual Machine (JVM):

- After compilation, the bytecode is executed by the Java Virtual Machine (JVM). The JVM is a runtime environment that interprets bytecode and manages memory, security, and other runtime aspects of Java programs.
- The JVM translates bytecode into native machine code instructions specific to the underlying hardware and operating system on which it's running. This translation is done dynamically during program execution.
- Additionally, modern JVM implementations often employ Just-In-Time (JIT) compilation techniques. JIT compilation involves translating frequently executed bytecode sequences into native machine code for improved performance.