What Are Gems?
Learn about RubyGems, the package management system for Ruby.
What Are Gems? is a free Ruby Academy lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Ruby Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
1
What Are Gems?
Gems are reusable libraries that add functionality to Ruby applications.
RubyGems is the package management system for installing and managing gems.
2
What is RubyGems?
RubyGems is the standard package manager for Ruby.
It helps install, update, and manage Ruby gems efficiently.
3
Checking Installed RubyGems Version
Use the following command to check your installed RubyGems version.
gem -v4
Listing Installed Gems
Use the gem list command to see installed gems.
gem list5
Updating a Gem
To update a gem to the latest version, use:
gem update gem_name6
Viewing Gem Details
Use the following command to see more details about an installed gem:
gem info gem_name7
Checking RubyGems Sources
View the gem repositories your system is using with:
gem sources8
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Alternatives to RubyGems
Other tools for managing Ruby dependencies include:
- Bundler: Manages gem dependencies for projects.
- RVM (Ruby Version Manager): Handles Ruby versions and gemsets.
- rbenv: Manages multiple Ruby versions.
10
Congratulations!
You have learned what Ruby gems are and how they are managed with RubyGems.
Next, you will learn how to install and use gems in your projects.
Frequently asked questions
Is the “What Are Gems?” lesson free?
Yes — the full text of “What Are Gems?” is free to read here on the web, and the Ruby Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Ruby Academy course, upgrade to CoddyKit PRO.
What will I learn in “What Are Gems?”?
Learn about RubyGems, the package management system for Ruby. 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; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “What Are Gems?” 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.