Currying is the technique of transforming a function  that takes multiple arguments into a function  that takes a single argument.

// Scala - Currying
object Demo {
  def add(x:Int, y:Int) = x + y
  def add2 (x : Int) = (y : Int) => x + y;  
  def add3 (x :Int) (y : Int) = x +y ;
  def main(args: Array[String]) {
    println(add(20, 10));    
    println(add2(20)(10));
    val sum40 = add2(40);
    println(sum40(50));
    println(add3(100)(200));
    val sum50 = add3(50)_;
    println(sum50(400));
  }
}