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Swift Array is ordered, growable, typed, value-semantics:

var nums = [1, 2, 3, 4]
print(nums.count)         // 4
print(nums[0])             // 1
nums.append(5)
nums.removeFirst()
print(nums.contains(3))    // true

Iterate with for ... in:

for n in nums { print(n) }
for (i, n) in nums.enumerated() { print("\(i): \(n)") }

All the functional methods are there:

nums.map { $0 * 2 }
nums.filter { $0 > 2 }
nums.reduce(0, +)
nums.sorted()                       // returns new sorted array
nums.sorted { $0 > $1 }              // descending

To declare an empty typed array: var nums: [Int] = [] or var nums = [Int](). Indexing past the end crashes — use .first, .last, or check .indices.contains(i) for safety.