Here is how you might define a class in Ruby:

class Greeter
  def initialize(name)
    @name = name
  end

  def say_hi
    puts "Hi !"
  end
end

And here is an arrow function in JavaScript:

const greet = (name) => {
  console.log(`Hello, ${name}!`);
}

Detailed Explanation

This lesson covers complex topics that require in-depth analysis.

Key Concepts

1. Abstraction: Hiding complex implementation details.
2. Encapsulation: Bundling data and methods.
3. Inheritance: Deriving new classes from existing ones.

"Simplicity is the soul of efficiency." – Austin Freeman

We will explore these concepts with practical examples.