NSUserDefaults
An NSUserDefaults is the same code like an ini-files.
You can store ans load a variable with a key.
With this functions, you can store values in the plist-file (properties)

Examples for save:
let nr:Int=41
let defaults=NSUserDefaults.standardUserDefaults()
defaults.setObject(nr,forKey: "nr")
defaults.setInteger(nr,forKey: "nr")
let str:String="Norman Bates"
let defaults=NSUserDefaults.standardUserDefaults()
defaults.setObject(str,forKey: "name")

Examples for load:
var nr:Int=0
let defaults=NSUserDefaults.standardUserDefaults()
nr=defaults.integerForKey("nr")
// a int, float or a double has ever a value, if the key not exist, you get the number 0
var str:String=""
let defaults=NSUserDefaults.standardUserDefaults()
str=defaults.stringForKey("name")!
// a string can be nil !!!

Function for save:
defaults.setObject(nr,forKey: "nr")

Function for load:
let nr:Int=defaults.integerForKey("nr")
let b:Bool=defaults.boolForKey("withShadow")
let myArray[Int]=defaults.arrayForKey("myArray")
let value:Float=defaults.floatForKey("price")
let value:Double=defaults.doubleForKey("price")
let obj:AnyObject=defaults.objectForKey("custom")
let strArray:[AnyObject]=defaults.stringArrayForKey("customs")

Function for save:
defaults.setObject(str,forKey: "name")
defaults.setBool(true,forKey: "withShadow")
defaults.setInteger(1234,forKey: "age")
defaults.setFloat(12.34,forKey: "price")
defaults.setDouble(12.34,forKey: "price")
defaults.setObject(myArray,forKey: "customs")
defaults.setObject(myDictionary,forKey: "customs")