Not exactly. Let's tweak your example to create a new object in your method. def foo s s = 'foo' end a = 'bar' foo a puts a # => bar The assig

Not exactly. Let's tweak your example to create a new object in your method. def foo s s = 'foo' end a = 'bar' foo a puts a # => bar The assignment in the method doesn't change the object you "passed" in. Rather than passing by reference, think of Ruby as passing the value of a reference. For more examples and explanation, see http://khelll.com/blog/ruby/ruby-pass-by-value-or-by-reference/ http://khelll.com/blog/ruby/ruby-pass-by-value-or-by-referen...