Set vs Array

The main difference is that NSArray is an ordered collection and NSSet is an unordered list of unique elements.

Set

• Primarily access items by comparison   

E.g    let ingredients = [“Tea Powder”, “Sugar”, “Hot Water”, “Milk”, "Cardamom"]

          if ingredients.contains(“Cardamom”) {

print(“It is Cardamom Tea”)
}

• unordered
• does not allow duplicates

Array

• Can access items by Index
• Ordered
• Allow duplicates