Do Hard Drives always spin?

[Maximous]

Do Hard Drives always spin, or do they have a "spin down when not in use" feature.

Question came up when looking at Vista Power Setting...all the way back to Dos 3.1 it never occured to me that HD didn't stop spinning. I always thought HD stopped spinning when not in use, the I realized when I warm boot a machine, I wait until the HD's stop spinning.

 

[Syntonic]

The OS has the feature to power down the hard drives after a certain amount of time otherwise they jus' keep on spinnin'. There are some arguments that starting and stopping the HD may cause as much problems as letting them run all the time - I personally leave them on.

 

[Maximous]

Thanks...it just never occured to me that they would spin unless "asked."