Confusion regarding OMM1

Hi all ,

Actually , I'v a couple of confusion regarding OMM1 tcode functionality .

1. Assignment of storage unit type to storage type -

here we have to assign one storage type to different storage unit type . Storage unit type , we define earlier . but my asking is , on what basis a storage type assigns with different storage unit type ?? - there's any parameter / rule ??

2 .

Assignment of storage unit type to storage bin type ...

A bin type assigns with different unit types . But , in LS10 for bin creation , we only assign  bin type .... then how , could we interpret bin type assignment with storage unit type ?? ...

thanks in advance ,

regards

arghya