Module Basics

Module Basics

A module is defined with module ModuleName ... end, grouping related methods, constants, and classes together, similar to a class but without the ability to be instantiated with .new. Modules serve two main purposes: namespacing (organizing related code) and mixins (sharing behavior across classes). They're a core part of how Ruby avoids needing multiple class inheritance.

Note: Trying to call SomeModule.new raises a NoMethodError -- modules cannot be instantiated directly, unlike classes.

Example: Module Basics

module MathHelpers
  def self.square(n)
    n * n
  end
end

puts MathHelpers.square(6)