What type of data collection have I created?

Hi there, I'm trying to get to grips with Swift as my first programming language, but I'm struggling a little to get my head around the terminology.

I've managed to create some kind of data collection with the following code:

let person1 = (name: "Mark", stats: ["Height": 190, "Weight": 180, "Age": 24])

let person2 = (name: "Dave", stats: ["Height": 186, "Weight": 175, "Age": 29])

but I'm not sure what this is. Is this a Tuple consisting of a String and a Dictionary? Or is there a better description of it?

I can then pass this construct into a function such as:

func compareAge(firstPerson : (name: String, stats: Dictionary<String, Int>), secondPerson: (name: String, stats: Dictionary<String, Int>))-> (name: String, stats: Dictionary<String, Int>){

if firstPerson.stats["Age"] > secondPerson.stats["Age"]{
    println("\(firstPerson.name) is older!")
    return (firstPerson)}
else  {
    println("\(secondPerson) is older!")
    return (secondPerson)}

}

It all seems to work, but it feels like there's a more elegant way of passing the required arguments into the function and specifying a return but without being sure of the terms, it's hard to find where to start reading up on it!

Hope this makes sense!

Cheers

Mark