Swift is a general-purpose programming language that's approachable for newcomers and powerful for experts. It is fast, modern, safe, and a joy to write.

struct ScientificName: Codable {
    var genus: String
    var species: String
    var subspecies: String?
}

let momiji = ScientificName(genus: "Acer", species: "palmatum")
let jsonData = try JSONEncoder().encode(momiji)

// {"genus":"Acer","species":"palmatum"}

struct ScientificName {
    var genus: String
    var species: String
    var subspecies: String?

    var description: String {
        var text = "\(genus) \(species)"
        if let subspecies {
            // subspecies is guaranteed to be non-nil here.
            text += "subsp. \(subspecies)"
        }
        return text
    }
}

func squareWave(phase: Float, overtones: UInt) -> Float {
    return (0...overtones)
        .map {
            let harmonic = Float($0 * 2 + 1)
            return sinf(phase * harmonic) / harmonic
        }
        .reduce(0, +)
}

let hello = "Hello, world!"
let multilineString = """
                  @@@         
      @@          @@@@       
    @@  @@@         @@@@@     
    @@@@@@@@@       @@@@@    
      @@@@@@@@@@    @@@@@@   
        @@@@@@@@@@  @@@@@@   
          @@@@@@@@@@@@@@@@@  
@           @@@@@@@@@@@@@@@  
@@@@@@        @@@@@@@@@@@@@  
  @@@@@@@@@@@@@@@@@@@@@@@@@@ 
    @@@@@@@@@@@@@@@@@@@@@@@@ 
        @@@@@@@@@@@@@     @ 
                      \(hello)
"""

Use Cases

• Apple Platforms

  Swift is a powerful and intuitive programming language optimized when running on iOS, macOS, and other Apple platforms.
  
  Apple offers a wide variety of frameworks and APIs that make applications developed for these platforms unique and fun.

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• Cross-platform Command-line

  Writing Swift is interactive and fun, the syntax is concise yet expressive. Swift code is safe by design and produces software that runs lightning-fast.
  
  SwiftArgumentParser and Swift's growing package ecosystem make developing cross-platform command-line tools a breeze.

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• Server and Networking

  Swift's small memory footprint, quick startup time, and deterministic performance make it a great choice for server and other networked applications.
  
  SwiftNIO and Swift's dynamic server ecosystem bring joy to developing networked applications.

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Getting Involved

Everyone is welcome to contribute to Swift. Contributing doesn’t just mean writing code or submitting pull request — there are many different ways for you to get involved, including answering questions on the forums, reporting or triaging bugs, and participating in the Swift evolution process.

No matter how you want to get involved, we ask that you first learn what’s expected of anyone who participates in the project by reading the Community Overview. If you’re contributing code, you should also know how to build and run Swift from the repository, as described in Source Code.

• Design

  Help shape the future of Swift by participating in the Swift evolution process.

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• Code

  Contribute to the Swift compiler, standard library, and other core components of the project.

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• Troubleshoot

  Help improve the quality of Swift by reporting and triaging bugs.

  Learn more

What’s New

Stay up-to-date with the latest in the Swift community.