anchor.diff:  
   . What does this concept mean?
   
  -. What benefits does it provides?
  -
  -. When to use them?
  +. What benefits does it provides? or when to use them?
   
   With this in mind, lets start with our topic.
   
  
positive.code: . The way we did not provide the third argument value. The syntax `_:Int` means I am not providing the third value which is of type `Int`
  . The function `partialSum2ArgumentsProvided` did not return any value but a function
  
  There are other http://stackoverflow.com/a/8001065/379235[uses] of `_` just in case you are curious but for the purposes of this example, all it means that I do not provide the value when I apply function.
  
  `<function1>` represents a Scala http://www.scala-lang.org/api/current/#scala.Function1[trait] which basically means "a function of 1 parameter."
  
negative.code: res1: Int = 6
  ----
  
  Aha!, so when we called/applied `3` to our we got our value result `6` back. But how come it knows about `1` and `2`? 
  
  Remember when we created `partialSum2ArgumentsProvided` we applied arguments `1` and `2`? That is how.
  
  It may be confusing, but try some other examples so that you can understand it.
  
  Taking this concept even further, you may want to ignore some or all of the arguments. Lets see how  
  
  [source, scala]
  ----
  scala> val partialSum1ArgumentsProvided = sum(1, _:Int, _:Int)
  partialSum1ArgumentsProvided: (Int, Int) => Int = <function2>
  
  scala> partialSum1ArgumentsProvided(2,3)
  res2: Int = 6
  ----
  
  and  
  
  [source, scala]
  ----
  scala> val partialSumNoArgumentsProvided = sum(_:Int, _:Int, _:Int)
  partialSumNoArgumentsProvided: (Int, Int, Int) => Int = <function3>
  
  scala> partialSumNoArgumentsProvided(1,2,3)
  res3: Int = 6
  ----
  
  ==== What ia