What is the difference between reference and value types in Swift?

In Swift, data types are divided into value types and reference types.

• Value types (for example, struct, enum, tuples) are copied when assigned or passed to a function. This means each variable has its own independent copy of the data.

• Reference types (classes class) pass a reference to the same object in memory when assigned or passed. Changes through one reference will be visible through others.

Example:

struct Point {
    var x: Int
    var y: Int
}

class Person {
    var name: String
    init(name: String) {
        self.name = name
    }
}

var p1 = Point(x: 0, y: 0)
var p2 = p1
p2.x = 10
print(p1.x) // 0, because p2 is a copy of p1

var person1 = Person(name: "Alice")
var person2 = person1
person2.name = "Bob"
print(person1.name) // Bob, because person2 and person1 refer to the same object

Thus, the difference is that value types are copied, while reference types pass a reference to the same object.