title: Difference between reduce and fold
body: <p>Reading this article about reduce vs fold in Scala <a href="http://josephmoniz.github.io/blog/2013/04/04/scala-reduce-vs-fold/">http://josephmoniz.github.io/blog/2013/04/04/scala-reduce-vs-fold/</a> it states "you are taking some value of N and performing aggregation operations on it such that the end result is typically some value of &lt;= N."</p>
  
  <p>But is this statement false since summing over N values produces a value >= N ?</p>
  
  <p>Update : I think &lt;= in this case means same type or sub-type</p>