Lecture 01 · Fundamentals

Introduction to Ruby & Setup

Beginner ~45 min

What is Ruby?

Ruby is a dynamic, open-source, object-oriented programming language known for its elegant syntax and developer happiness. It powers Ruby on Rails, one of the most productive web frameworks.

Why Ruby?

Beautiful, readable code
Extremely productive
Excellent for web development with Rails
Strong community and ecosystem

Installation

Use rbenv or RVM (recommended) or install via Homebrew on macOS.

terminal

ruby --version
irb   # Interactive Ruby shell

Your First Ruby Program

hello.rb

puts "Hello, Ruby Mastery!"
puts "Ruby is fun and productive!"

Output

Hello, Ruby Mastery!
Ruby is fun and productive!

🎯 Exercise 1.1

Create hello.rb and run it with ruby hello.rb. Then try the interactive shell with irb.