What is the difference between an array and a set?

An array is an ordered collection of elements of the same type, allowing duplicates. Elements are accessible by index.

A set is an unordered collection of unique, hashable values. Duplicates are not allowed.

Key differences:

Attribute	Array	Set
Order	Yes	No
Duplicates	Allowed	Not allowed
Access	By index	Check for element presence
Performance	Fast index access, slow insertion/deletion in the middle	Fast add/remove and check operations

Example of creation:

// Array
var numbersArray: [Int] = [1, 2, 2, 3, 4]

// Set
var numbersSet: Set<Int> = [1, 2, 3, 4]