Difference between last(X) and latest(X)

Hi,

What is the difference between last(X) and latest(X) functions for stats. I tried both in searches and i get same output. The difference is not quite clear in splunk documentation http://docs.splunk.com/Documentation/Splunk/latest/SearchReference/CommonStatsFunctions

I would like to know the exact difference between these two functions.

Thanks

Strive