Plan Version vs. Expert Mode

Hello Experts,

I am a bit confused between the Plan Versions where in we can maintain "X" number of plan versions depending upon your company's strategies to expand/downsize vis a vis the future business plan.

In expert mode [T-code PO10/PO13] also i see the tab pages

ACTIVE/PLANNED/SUBMITTED/APPROVED/REJECTED

Could any one explain to me the differences between these things?

Also if i am to move an object from ACTIVE to PLANNED or from PLANNED to SUBMITTED in Expert Mode, how do i do it at the SPRO level.

Regards

Bijoy Yohannan