Hi Apeksha, Process studio is the workspace where the flow of the process is defined. When a page of a process is run, it will run from the main page irrespective of whatever the page you are in. While Object studio is the workspace where the objects of the applications have interacted. When a page in the object is run, it will run only the current page.
Different stages in Process Studio are: Link, Block, Process, Page, Action, Decision, Choice, Calculation, Multi Calculation, Data Item, Collection, Loop, Note, Anchor, End, Alert, Exception.
Different stages in Object Studio are: Link, Block, Read, Write, Navigate, Code, Wait, Process, Page, Action, Decision, Choice, Calculation, Multi Calculation, Data Item, Collection, Loop, Note, Anchor, End, Exception.