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Often times I leave my computer on while waiting for a process, such as a large download, to complete. It's a superstition of mine to turn the computer off as soon as possible after the task has completed. Do computers need "breaks" or can they be left running indefinitely? In particular I'm wondering about the hard drive if it's always spinning while the machine is powered on wouldn't that mean it wares out faster if always on?
I am not asking if it's ok to always leave it on, I am asking should one make the effort to shut it down as much as possible?