Swift

What is Swift?

Swift is an open-source, statically typed, compiled programming language created by Chris Lattner at Apple. Development began as a personal project in 2010, the language was announced publicly at WWDC in June 2014, and Apple open-sourced it in December 2015. Swift is Apple's modern replacement for Objective-C, the primary language for building iOS, macOS, watchOS, and tvOS apps.

Swift compiles via LLVM straight to fast native machine code, and its defining feature is Optionals — a type-safe way of representing "no value" that forces developers to handle missing data explicitly, eliminating an entire category of null-pointer-style crashes at compile time instead of at runtime.

Where is Swift Used?

Swift is the default language across Apple's entire platform ecosystem, and it is steadily expanding beyond it. Here are the major application areas:

Real-World Examples

Here are some practical applications you can build using Swift:

Why Learn Swift?

Code Example

Here is a small taste of what Swift looks like — a struct with an optional property, and guard let used to safely handle a missing value:

struct Student {
    let name: String
    let marks: Double?
}

func grade(_ student: Student) -> String {
    guard let marks = student.marks else {
        return "\(student.name): No marks recorded"
    }
    return marks >= 60 ? "\(student.name): First Class" : "\(student.name): Pass"
}

let students = [
    Student(name: "Rahul", marks: 78.5),
    Student(name: "Meera", marks: nil)
]

for student in students {
    print(grade(student))
}

Course Curriculum

Follow these 12 lessons sequentially to build a solid, practical foundation in Swift.

Projects You'll Build

Apply your knowledge by building these real-world projects:

Frequently Asked Questions

Key Takeaways & Summary