What are value types in Swift and how do they relate to data types?

Value types in Swift are types whose value is copied when assigned to a variable or constant, as well as when passed to a function. Each instance of a value type stores its own copy of data.

Value types in Swift include:

• Structures (struct)
• Enumerations (enum)
• Tuples (tuple)
• Basic data types:
  • Numeric types (Int, Double, Float, Bool, etc.)
  • Strings (String)
  • Arrays (Array)
  • Dictionaries (Dictionary)
  • Sets (Set)

Example:

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

var p1 = Point(x: 1, y: 2)
var p2 = p1 // Copying the value of p1 into p2
print("p1: \(p1.x), \(p1.y)") // p1: 1, 2
print("p2: \(p2.x), \(p2.y)") // p2: 1, 2

p2.x = 10 // Changing p2 does not affect p1
print("p1 after changing p2: \(p1.x), \(p1.y)") // p1 after changing p2: 1, 2
print("p2 after changing p2: \(p2.x), \(p2.y)") // p2 after changing p2: 10, 2