Can you explain the differences between Nil and Null in programming?

In programming, Nil and Null are often used to denote the absence of a value, but their meaning and usage can differ depending on the language.

• Null usually means that a variable explicitly does not refer to any object or value. For example, in languages like Java, C#, SQL — it is a special value indicating the absence of data.

• Nil is often used in languages like Objective-C, Swift (before Optional), Ruby, Lua and means the absence of an object or emptiness. In Swift, Nil is an Optional value indicating the absence of a value.

Example in Swift:

var name: String? = nil // variable can contain a string or nil
if name == nil {
    print("Value is missing")
}

Thus, Nil and Null are conceptually similar, but the terminology and details depend on the specific language and its type system.