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Ruby Cheat Sheet

Print-ready cheat sheet for Ruby, organized for fast lookup, study, and desk-side use

Source: Ruby Documentation (ruby-lang.org)
License: MIT
Variants: 3 download options
Updated: 2026-03-27

Sample

What's in this cheat sheet

Hello World

puts "Hello, World!"
print "no newline"
p [1, 2, 3]   # inspect output: [1, 2, 3]

Run Ruby

ruby script.rb          # run a file
ruby -e 'puts "hi"'    # run inline
irb                     # interactive REPL

Variables

`name`	Local variable
`@name`	Instance variable
`@@count`	Class variable
`$debug`	Global variable
`MAX_SIZE`	Constant (uppercase by convention)

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