I am trying to learn a little Ruby. Can someone please explain to me the difference between these two examples? 

Say that I have a hash: 

```
family = { "Homer" => "dad",
  "Marge" => "mom",
  "Lisa" => "sister",
  "Maggie" => "sister",
  "Abe" => "grandpa",
  "Santa's Little Helper" => "dog"
}

```

If I iterate like this:

```
family.each { |x| puts "#{x}" }

```

I get this:

```
["Homer", "dad"]
["Marge", "mom"]
["Lisa", "sister"]
["Maggie", "sister"]
["Abe", "grandpa"]
["Santa's Little Helper", "dog"]

```

When I iterate like this:

```
family.each { |x, y| puts "#{x}: #{y}" }

```

I get this:

```
Homer: dad
Marge: mom
Lisa: sister
Maggie: sister
Abe: grandpa
Santa's Little Helper: dog

```

Can someone please explain how the two results differ (what do the square brackets, quotes, commas, colons mean?), and when one might use one vs. the other? Thank you!