Ruby Academy · Lesson

Loops and Iterators

Master looping techniques like while, until, for, and iterators such as each to repeat tasks.

Lesson 2 of 310 steps

Loops and Iterators is a free Ruby Academy lesson on CoddyKit. This is lesson 2 of 3. Any 3 lessons of this learning path are free to read in full — after that, CoddyKit PRO unlocks every lesson, plus hands-on practice with a built-in code editor and a 24/7 AI tutor. It is part of the Ruby Academy learning path, and your progress syncs across the web and the CoddyKit app. The Ruby Academy course includes 3 lessons in total.

Loops and Iterators

Loops allow your Ruby programs to repeat actions efficiently.

In this lesson, you will learn how to use loops like while, until, for, and iterators like each.

Using While Loop

The while loop repeats a block of code while a condition is true.

count = 1
while count <= 5
  puts count
  count += 1
end

Using Until Loop

The until loop runs until the condition becomes true.

count = 1
until count > 5
  puts count
  count += 1
end

Using For Loop

The for loop is useful for iterating over a range.

for i in 1..5
  puts i
end

Using Each Method

The each method iterates over an array or range.

[1, 2, 3, 4, 5].each do |num|
  puts num
end

Using Loop Statement

The loop method runs indefinitely unless stopped.

i = 1
loop do
  puts i
  i += 1
  break if i > 5
end

Break and Next in Loops

break exits a loop, and next skips to the next iteration.

for i in 1..5
  next if i == 3
  break if i == 5
  puts i
end

Answer it in the interactive lesson

Using Map for Transformation

The map method transforms each element in a collection.

numbers = [1, 2, 3, 4, 5]
squares = numbers.map { |n| n * n }
puts squares

Congratulations!

You have learned different types of loops and iterators in Ruby.

Next, you will learn about logical and comparison operators.

Free to start

Learn Ruby with an AI tutor — free

Write and run real code in your browser, get instant help from a 24/7 AI tutor, and pick up where you left off on the web or in the app.

Courses: 29
Lessons: 109

Start learning free View the full course

Frequently Asked Questions

Is the “Loops and Iterators” lesson free?

Yes — any 3 lessons of the Ruby Academy learning path, including “Loops and Iterators”, are free to read in full here on the web. After that, CoddyKit PRO unlocks every lesson, plus interactive practice with a built-in code editor and a 24/7 AI tutor. The Ruby Academy course includes 3 lessons in total.

What will I learn in “Loops and Iterators”?

Master looping techniques like while, until, for, and iterators such as each to repeat tasks. You practise Ruby Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start Ruby Academy?

No prior experience is required. Ruby Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 2 of 3.

How long does the “Loops and Iterators” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this Ruby Academy lesson?

Yes. Every Ruby Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

All lessons in this course

← Back to Ruby Academy