Which protocol is used to implement data transfer in Swift?

In Swift, data transfer is usually implemented through protocols that define the interaction interface. However, when it comes to network data transfer, iOS uses the HTTP/HTTPS protocol over TCP/IP, and network interaction in Swift is done through URLSession and related classes.

If the question concerns data transfer between objects in Swift, the Codable protocol is often used for serialization and deserialization of data, as well as delegation protocols for event passing.

Example of using URLSession to load data:

let url = URL(string: "https://example.com/data.json")!
let task = URLSession.shared.dataTask(with: url) { data, response, error in
    if let data = data {
        // process received data
        print(String(data: data, encoding: .utf8) ?? "")
    }
}
task.resume()