What Is a Function in Scala

Scala treats functions as first-class objects with an `apply` method, which helps explain how function calls work under the hood.

The article covers Scala’s `FunctionX` traits such as `Function1` and `Function2`, along with the `=>` syntax and lambda-style function literals.

It also shows how one- and two-argument functions are written in practice, including a custom `MyFunction` example.

A key takeaway is the difference between `val`-defined function values and `def` methods, which matters for higher-order functions and functional design.