My Aunt Rose, no longer an octogenarian because she proudly points out as of this summer she is a nonagenarian, asks this week’s question as she familiarizes herself with her new laptop and its newer version of Windows. “On the computer, what is the difference between hibernate and sleep?” she emails me to ask.
Hibernate and sleep are two states situated between on and off. Everyone already understands that if any electric appliance is on it can be turned off. Likewise when a computer is on it can be turned off, but being a more sophisticated device the computer offers some in-between options.
Sleep is a state in which most of a computer’s operations are placed in a minimum power consumption state to save the battery. Hard disks are powered down, screen turned off, and memory chips are placed on hold. When you “wake up” your computer, it boots very quickly because it was actually still on. While sleeping, the computer is still running basic functions.
Hibernation is the state of taking everything that is active in RAM, including programs, open windows, etc. and freezing the current state of the computer into a special file on your hard drive. Once everything is saved to this file, the computer powers off and shuts down completely.
In either case, a computer that is hibernating or sleeping will return to its previous state when it is waked by turning it back on. Besides the battery and power consumption considerations already described, there are several other differences between sleep and hibernate.
Putting a computer to sleep is much faster than hibernating. A sleeping computer wakes up much faster than returning from hibernation. If you are going to be away from the computer for a few minutes then sleep might be the best choice.
Hibernation turns the computer completely off, so this is probably the best choice when you plan to leave the computer off for longer than several hours. A sleeping computer would eventually run the battery down whereas a hibernating computer would not.
There is also something called “hybrid sleep mode” for desktop computers; Mac OS-X calls this mode “safe sleep.” This mode saves your work as if hibernating but then sleeps the computer. Hybrid sleep mode is used for desktop computers which unlike laptops do not have batteries and would otherwise loose the sleep state if there were a power outage.
In Microsoft Windows the Power Options are found in the Control Panel. Click on the selected “Change Plan Settings” to find the window where you may configure the inactivity time after which the computer automatically enters sleep mode. Back in the Power Options window, on the left sidebar should be found a link for “Choose what closing the lid does.” I have my laptops configured to hibernate when I press the power button or to sleep when I close the lid. This gives me the option to use either mode as is appropriate.
Mac OS-X users will find their power options settings by clicking the apple then Preferences then “Energy Saver.” Apple provides only the option to use sleep mode. Mac laptops enter sleep mode when the lid is closed or when the option is selected from the apple pull-down menu. Technically there is a hibernation-like feature in OS-X called “Resume” available from the menu, and Mac laptops automatically kick into this hibernation mode when the battery is low.
Something to keep in mind about both hibernation and sleep, and whether using Windows or Mac, is that only your local work will be saved. If you close the lid of your laptop while playing a game of Solitaire your positions will be saved. If you were in the middle of writing an email on the Gmail, Yahoo, or Hotmail web page, that email you were writing will be lost and you will need to log onto your email account page to start over.
A personal note: The day before this column was submitted for publication, my Aunt Rose unexpectedly passed away. A member of a pioneering Texas newspaper family, Rose Usry worked in the news business for many decades and in retirement made her home in San Luis Potosi from where she continued certain editing duties. Every week without fail I received an email from Aunt Rose contributing her editorial advice to the writing of this column. This one is the last. Without her helping hand my spelling, grammar and punctuation may be a bit rough around the edges.