the computer is on and the cpu is running
step 1-the computer is not runnig however the cpu and ram are still recieving power
Step 2- the cpu is off but the ram is refreshed. the system is in a lower mode than step 1
Step 3-the cpu is off and the ram is set to a slow refresh rate . this mode is often called save to ram in windows xp this state is known as the standby mode
Step 4-the cpu and ram are off. the content of ram have been saved to a temporary file on the hard disk. this mode is also called dsaved to disk in windows xp this state is known as the hibernate mode
Step 5-the computer is off and nothing has been saved 
