Safe sleep was made after noticing whenever Yahoo Messenger was running and sleep mode was initiated
Yahoo Messenger would break the internet connection after coming out of system sleep mode.
it was set not to sign in automatically it would try to reconnect if it was running beforehand regardless
of what it was instructed to do.
Without using Safe Sleep it would break the connection every time if your computer was in sleep mode for any significant length of time.
What Safe Sleep does is shut down one application before your computer sleeps automatically so that when it awakes your computer can connect to the internet without another application hammering it until it successfully blocks your internet connection and you have to restart your computer and close a number of applications that you were trying to keep open in the first place.