If you're wondering what Steven's actually doing here he's iterating over an array and passing each element to a block. The block uses [#send](http://ruby-doc.org/core-2.1.0/Object.html#method-i-send), which is an instance method defined on ```Object``` in Ruby that takes a symbol argument corresponding to the method name you want to call and then passes all subsequent args as args to that method. So basically he's doing the equivalent of this:

```ruby
Chef::Recipe.include(::Extensions)
Chef::Resource.include(::Extensions)
```

Include is a class method that is available on any class to open up the class and add the methods from the class passed in as an argument. The double colon at the beginning means Steven wants the top level Extensions class and not one inside a module namespace (e.g. Chef::Resource::Extensions)