The Basic Structure of the Ruby Method

As we have seen, the basic structure of a method is as follows:

def echo(var)
  puts var
end

We are defining a method named echo that accepts the var variable as a parameter or argument. The end keyword marks the end of the block of code. The code between the def and end statements is known as the method body or the method implementation.

Methods are always called on an object. In Ruby, a method is called a message, and the object is called the receiver. The online Ruby documentation uses this language specifically, so it is good to get used to this vocabulary.

In the previous example, however, it doesn't seem like there is an object. Let's investigate this through IRB:

def echo(var)
  puts var
end
=> :echo
echo "helloooo!"
helloooo!
=> nil
self
=> main
self.class
=> Object

Here, we've defined and called our echo method in IRB. We use the self keyword, which is a reference...