You found it first ⚡ 50% off any plan for 6 months, exclusive to new subscribers for a limited time only.

Join the Treehouse affiliate program and earn 25% recurring commission!

✨ Earn college credits in Cybersecurity, JS, HTML, CSS and Python

🌟 Dreaming of a bright future? 🎓 Ask about the Treehouse Scholarship program! 🚀

  • Treehouse Logo
  • Plans
    Chevron
    • For Individuals
    • For Businesses
    • For Schools
    • For Libraries
    • For Military
  • Library
    Chevron
    • All Courses
    • Tracks
    • College Credit
  • Techdegree
    Chevron
    • Overview
    • Front End Development
    • Full Stack JavaScript
    • Data Analysis
    • UX Design
    • Python
  • Community
    Chevron
    • Code Adventures
    • Discord
    • Forum
    • Success Stories
    • Treehouse Links
    • 100 Days of Code
  • Resources
    Chevron
    • Career Toolbox
    • CodeForward
    • Free Treehouse Near Me
    • Jobs
    • Blog
    • Support
    • About
  • For Individuals For Businesses For Schools For Libraries For Military
  • All Courses Tracks College Credit
  • Overview Front End Web Development Full Stack JavaScript Python Development Data Analysis UX Design
  • Code Adventures Discord Forum Success Stories Treehouse Links 100 Days of Code
  • Career Toolbox CodeForward Free Treehouse Near Me Jobs Blog Support About
  • Sign In
  • Free Trial
Instagram Twitter Facebook YouTube LinkedIn
    • Newest
      • Newest
      • Active
      • Unanswered
      • Featured
    • All Topics
      • All Topics
      • • General Discussion
      • • AI
      • • Android
      • • APIs
      • • Coding for Kids
      • • College Credit
      • • Computer Science
      • • CSS
      • • Data Analysis
      • • Databases
      • • Design
      • • Development Tools
      • • Digital Literacy
      • • Game Development
      • • Go Language
      • • HTML
      • • Java
      • • JavaScript
      • • Learning Resources
      • • Machine Learning
      • • No-Code
      • • PHP
      • • Professional Growth
      • • Python
      • • Quality Assurance
      • • React
      • • Ruby
      • • Security
      • • Swift
      • • Vibe Coding
  • nathanielcusano
    nathanielcusano
    9,808 Points

    Why does ruby -v have to be lowercase? I tried Ruby -v and it doesn't work.

    Posted March 20, 2017 11:04pm by nathanielcusano
    nathanielcusano
    9,808 Points
    • Ruby
    • Ruby Basics (Retired)
    • How Ruby Works
    • The Ruby Programming Language

    1 Answer

  • A X
    A X
    12,842 Points

    What does 'nil' signify?

    Posted April 16, 2016 3:30am by A X
    A X
    12,842 Points
    • Ruby
    • Ruby Basics (Retired)
    • How Ruby Works
    • The Ruby Programming Language

    2 Answers

  • michaelkoopmanschap
    michaelkoopmanschap
    7,443 Points

    How can I change the command line from vertical to horizontal?

    Posted July 29, 2014 12:26pm by michaelkoopmanschap
    michaelkoopmanschap
    7,443 Points
    • Ruby
    • Ruby Basics (Retired)
    • How Ruby Works
    • The Ruby Programming Language

    2 Answers

  • klaas foppen
    klaas foppen
    6,569 Points

    quotes don't seem to work

    Posted July 29, 2014 12:26pm by klaas foppen
    klaas foppen
    6,569 Points
    • Ruby
    • Ruby Basics (Retired)
    • How Ruby Works
    • The Ruby Programming Language

    4 Answers

Posting to the forum is only allowed for members with active accounts.
Please sign in or sign up to post.

    Treehouse

  • About
  • Blog
  • Careers
  • Community
  • Stories
  • Shop
  • Contact
  • Gift Card

See Full Catalogue

Techdegree

  • Front End Web Development
  • Full Stack JavaScript
  • Python Development
  • Data Analysis
  • UX Design

Tracks

  • Learn to Code for Beginners
  • Beginning Python
  • Beginning SQL
  • Beginning Java
  • ...see more

Courses

  • JavaScript Basics
  • Intro to HTML & CSS
  • Python Basics
  • CSS Layout
  • ...see more

Explore

  • Plans
  • Affiliates
  • Perks
  • Free Treehouse Near Me
  • Treehouse for Libraries
  • Treehouse for Businesses
  • Twitter
  • YouTube
  • Facebook
  • LinkedIn
  • Instagram
Terms & Conditions | Privacy

© 2025 Treehouse Island, Inc.