We know that methods in Ruby can return values, and we ask a method to return a value when we want to use it in another part of our program. What if we don’t put a return statement in our method definition, though?

For instance, if you don’t tell a JavaScript function exactly what to return, it’ll return undefined. For Python, the default return value is None. But for Ruby, it’s something different: Ruby’s methods will return the result of the last evaluated expression.

This means that if you have a Ruby method like this one:

def add(a,b)
  return a + b
end

You can simply write:

def add(a,b)
  a + b
end

And either way, when you call add(1,1), you’ll get 2.