Welcome to your first Ruby program! In this section, we will guide you through writing, running, and understanding a simple Ruby program. By the end of this lesson, you will have a basic understanding of how to create and execute Ruby code.

1. Open your text editor or IDE (Integrated Development Environment).
2. Create a new file and name it hello_world.rb. The .rb extension indicates that this is a Ruby file.

In your hello_world.rb file, type the following code:

• # This is a comment: This line is a comment. Comments in Ruby start with a # and are ignored by the Ruby interpreter. They are useful for adding notes or explanations within your code.
• puts 'Hello, world!': This line is a Ruby method that prints the string 'Hello, world!' to the console. puts stands for "put string" and is used to output text.

Save your hello_world.rb file.

1. Open your terminal or command prompt.

2. Navigate to the directory where you saved your hello_world.rb file. You can use the cd command to change directories. For example:

   cd path/to/your/directory
   

Run your Ruby program by typing the following command in the terminal:

You should see the following output in your terminal:

Congratulations! You have successfully written and executed your first Ruby program.

Modify the hello_world.rb program to print your name instead of "Hello, world!".

Solution

Replace [Your Name] with your actual name. Save the file and run it again using the ruby hello_world.rb command.

Add another puts statement to print a second line of text.

Solution

Save the file and run it again. You should see:

• Syntax Errors: Ensure that you use single or double quotes around strings. Missing quotes will result in a syntax error.
• File Naming: Make sure your file has the .rb extension. Without it, the Ruby interpreter may not recognize the file as a Ruby script.
• Terminal Navigation: Be careful with the cd command to navigate to the correct directory where your Ruby file is saved.

In this lesson, you learned how to:

• Create a new Ruby file.
• Write a simple Ruby program using the puts method.
• Run your Ruby program from the terminal.
• Modify and extend your program with additional output.

With these basics in hand, you are now ready to dive deeper into Ruby's syntax and structure in the next lesson. Keep practicing, and soon you'll be writing more complex Ruby programs with ease!