Swift
Build for Apple and beyond
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read 7 chapters Programming language
Created
2014 by Apple (Chris Lattner)
Type
Compiled, statically typed, safe
Runs on
iOS, macOS, watchOS, tvOS, Linux
Current version
Swift 5.10 (2024)
Powers
All Apple platform apps since 2014
Key feature
Optionals replace null
File extension
.swift
Best for
iOS/macOS apps, server-side Swift
What is Swift?
Swift is a modern programming language created by Apple in 2014 for iOS, macOS, watchOS, and tvOS development. It's also used for server-side development via Swift on Linux.
Why Swift?
Swift replaced Objective-C as Apple's primary language. It's safe (optionals prevent null crashes), fast (LLVM-compiled), and expressive (reads like natural language).
| Feature | Swift | Objective-C | Kotlin (Android) |
|---|---|---|---|
| Null safety | Optionals | Pointer-based | Nullable types |
| Performance | Excellent | Excellent | Excellent |
| Modern syntax | Yes | No (verbose) | Yes |
| Apple platforms | Primary | Legacy | Not supported |
| Server-side | Growing (Vapor) | No | Spring/Ktor |
What you'll learn
| Chapter | What you'll know |
|---|---|
| Introduction | What Swift is, variables, types |
| Optionals | Swift's solution to null |
| Structs | Value types, protocols, extensions |
Start with introduction.