Is it harmful at all when I shut down and unplug my iMac every night?

Question

The reason I am asking this question is because yesterday, my iMac shut off randomly by itself. 2 mins later I turned it back on, started searching about why a Mac might shut off by itself, then bam! Within 5 mins of turning it back on, it shut off by itself again.

So I unplugged it for the night, and then I looked up how to do an SMC reset/reboot and then did it.

Link: http://support.apple.com/kb/ht3964

Then I realized... I do an SMC reboot every single night because I first power off my iMac, turn off the power bar/strip, and unplug the power bar/strip from the outlet in hopes of saving a bit of energy during the night.

My questions are:

1. Is it harmful that I shut down and unplug my iMac every night? (basically reseting the SMC every night)

2. Is it better to just put the iMac to sleep instead of shutting it down, or is there rarely any difference?

Solution

1. nop
2. putting a mac to sleep let your resume faster. Shutting down a computer will clear everything in RAM, effectively solve many basic problems related to software instability(unresponsive app, memory leak, etc) So on your daily basis, you can just sleep it, but once in a while (depends on how intensive you use your computer) you should shutdown, or restart it. (I usually sleep my computer and reboot once every 3-5 days)

Comments

[HikeMike]

There are power meters you can put between a device and its power outlet. Don't just hope, find out how much it helps.

[Daniel R Hicks]

This doesn't apply if you're talking about a desktop system (which seems to be the case), but with a laptop you can get in a situation where the system detects that the battery is being overcharged and thus pulls the plug. The "fix" is to simply run the system on battery from time to time.

[Jacob]

I did a lot of searching about this today and it seems most people do let it sleep then restart it every couple of days or weeks. Thanks for another confirmation of that!