Your first Kotlin program

In this example, you’ll write, compile, and run a simple Kotlin application that prints “Hello, Kotlin!” to the console.

Prerequisites

- Java JDK 8 or newer installed
- Kotlin compiler on your PATH or an IDE with Kotlin support

Step 1: Create the Source File

Create a file named Hello.kt with the following content:

fun main() {
    println("Hello, Kotlin!")
}

Step 2: Compile

Open your terminal, navigate to the directory containing Hello.kt, and run:
kotlinc Hello.kt -include-runtime -d Hello.jar
This produces Hello.jar containing your compiled program and the Kotlin runtime.

Step 3: Run

Execute your program with:
java -jar Hello.jar
You should see:
Hello, Kotlin!

Next Steps

- Try modifying the println message
- Explore variables, functions, and control flow
- Use an IDE like IntelliJ IDEA to step through your code