WHAT IS Costing Version and What is the use ? (T.code : OKYD)

Hi Experts,

What is Costing Version and what is the use? Where we can assign this to our organization units? How system pick up to execute multiple cost estimates for the same material?

Note. I am not asking about Controlling Version (T.code :OKEQ). I asking about Costing Version (T.Code : OKYD) ?

Thanks

PBR