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Variables

Variables are named references to objects. Ruby has a variety of variable types and scopes.
Ruby
5 Articles in: Variables
Everything You Need to Know About Variables
Variables are named references to objects in memory. Their several variants (local, instance, class, constant, etc) each have their own subtleties.
Local Variables and Bindings
Ruby has a no-surprise take on local variables, they're handled similarly in most programming languages. However, Ruby implements them differently than stack-based languages.
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Instance Variables
Instance variables are some of the most common and important variables types in Ruby. They begin with the at sign (@) and allow objects to track their internal state.
Global Variables
Global variables are not often used in Ruby, however, you should at least understand their usage should you ever encounter them.
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A Quick Guide to Using Environmental Variables in Ruby
Using environment variables in Ruby.