by mulit threading many things can be done at once.
windows time slices the cpu time and allocates to each thread.
on expiring the time slice, thread is paused.
the state( CPU Registers and other data) of the thread is saved.
Another threading waiting for its slice will started. paused as above.
when it comes to the first threads time its is reloaded and resumed.
Can have base and dynamic priorities. base can be changed but not more than parent.
dynamic is same as base except can be raised or lowered by windows.
OS(win) chooses which thread to run next based on dynamic priority.
Every programm has a primary thread can be used to create other thread.
These objects are created by windows ojbect manager.