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Scala ("scalable language") was designed in 2003 at EPFL by Martin Odersky. Runs on the JVM, fully interoperable with Java. Heavily influenced functional programming adoption in industry.

A minimal program with a top-level App:

object Main extends App {
  println("Hello, Scala!")
}

The object Main is a singleton object. extends App provides a built-in main method whose body is the object's body.

Alternative explicit form:

object Main {
  def main(args: Array[String]): Unit = {
    println("Hello, Scala!")
  }
}

No semicolons needed. Comments use // and /* ... */.