When connected sequence of components of the same branch of graph execute concurrently is called pipeline parallelism.

Componets like reformat where we distribute input flow to multiple o/p flow using output index depending on some selection criteria and process those o/p flows simultaneosly creates pipeline parallelism.

But components like sort where entire i/p must be read befor a single record is writen to o/p can not achieve pipeline parallelism.

guys,

this was a very good question

before learning abinitio or building any graph u need to know the concepts of parallisms they are 1)data parallism 2)pipeline parallism 3)component parallism

generally pipeline parallism is a concept of processing of  data by different components

let me give u flow:

input file ------>reformat----->rollup------>filter by expression----->o/p file

                       50th record            25 records                10 records

 clearly speaking when ever u run any graph we observe the number of records processed on flows ,this is best example for pipeline parallism

hope this might suffices u

mukund