Do you know the difference between series and serials?
Basically, it is just as such:
Serial - usually fictional story; divided and broadcasted in parts; each part being a continuation of the previous part.
Example : Heroes, Chinese dramas
Series - need not be based on a work of fiction; set of related programmes each with a beginning, middle and end; each part does not carry over to the next.
Example : Friends, NYPD Blue, Discovery Channel's Sharks week