Computer takes too long to boot
A friend recently complained about how long his computer took to boot each time he switched it on. When I showed him the Sleep and Hibernate modes he immediately changed the default settings so his computer hibernated when he pressed the power button instead of shutting down.
This is exactly what I do with my work laptop, and indeed is what I’ve been doing since 2001. I also use Sleep when I’m only going to be away from my computer a short time (e.g. lunch, or walking to a meeting with my lapotp).
Both sleep and hibernate save the state of the computer so that when you next turn it on (or “resume”), the computer carries on where it left off; no need to start everything from scratch.
Hibernate saves the state to disk then turns the computer off, so it uses no power. Sleep saves the state in RAM which needs some power to work, so a small amount of power is consumed.
These features work irrespective of what Operating System you’re running (Windows XP, Vista, 7, Linux [e.g. Ubuntu] and Apple OSX ). Some boot more quickly than others (OSX vs Vista for example) but none are as fast as resuming from sleep or hibernate.
The only word of warning: reboot the computer once in a while (for me, thats a couple of times/month) to clear out garbage left from crashed programs.