nil is a special thing in Ruby.
It represents empty or nothing.
If we ask for a value from an
array and that value is not there,
then we get nil.
As expected, we see nothing in the console.
There is no 10th element in the array.
So, the array returns nil.
It means the 10th element is nothing.
Similarly, let's try to get a
value from a hash for which the
key is not there.
The hash does not have the key c.
So the hash returns a nil.