Programs and modules

// This import declaration binds the prefix `io` to the `ballerina/io` package. 
// The prefix by default comes from the last part of the package name.

// The `ballerina` org name is reserved for the Ballerina library packages.
import ballerina/io;

// `main` function is the program entry point. 
// `public` makes the function visible outside the package.
public function main() {
    // Here `io:println` means function `println` is in the package bound to prefix `io`.
    io:println("Hello, World!");
}