Arrays, Dictionaries & Sets

Collections let you store and organize multiple values. Swift provides three primary collection types: arrays (ordered lists), dictionaries (key-value pairs), and sets (unique unordered values). Each has different performance characteristics that determine when to use which.

Arrays

An array stores values of the same type in an ordered list:

var fruits = ["Apple", "Banana", "Cherry"]
fruits.append("Date")
print(fruits[0])  // Apple
print(fruits.count)  // 4

Full content for this chapter will be added in a future update. The complete article covers array operations, dictionaries, sets, performance (Big-O notation), and choosing the right collection type.