Exiting Windows Gracefully
When you've finished a Windows 7 session, you should properly shut down or log off to ensure that your work is saved and that no damage is done to the OS. Shall we reiterate? Shutting down properly is very important. You can lose your work or otherwise foul up Windows settings if you don't shut down before turning off your computer. If multiple people share the computer, you should at least log off when you're finished so that others can log on. Logging off protects your work and settings from prying eyes. When you shut down, Windows does some housekeeping, closes all open files, prompts you to save any unsaved work files, and alerts the network that you and your shared resources are no longer available for consultation.
You can always choose to shut down the computer; all or only some of this information might apply to your machine. Newer machines have more shutdown features because they're likely to have advanced power management built in to them via ACPI (Advanced Computer Power Interface).
These are the steps for correctly exiting Windows:
- Close any programs that you have running. (This can almost always be done from each program's File, Exit menu if the menu bar is active or by clicking the program's close button.) If you forget to close programs before issuing the Logout or Shut Down command, Windows attempts to close them for you. If you haven't saved your work, you're typically prompted to do so. You must close some programs, such as DOS programs, manually. Windows alerts you if it can't automatically close an open program. Quit the DOS program and type exit at the DOS prompt, if necessary. If you are just switching user context, your open application's status is saved so you can quickly return to it later.
- Click Start, and then move the mouse over the right-arrow button to the right of the Shut Down button. You'll see the menu shown in Figure 4.15.
Figure 4.15 The Shut Down selection menu.
- Click on the desired option.
Consider these points:
- The Hibernate option records the current state of the system to disk and then shuts down the computer. When the power is turned back on, the system reboots. If you log back in as the same user who initiated the hibernation, the system returns to its exact state at the moment of hibernation.
- If you want to log off, expand the Shut Down menu and select Log Off.
- If you attempt to shut down the computer while another user's desktop is still active (that is, you choose Switch User and at least one other user is still logged on), you'll see a warning message stating that performing a shutdown could result in data loss, along with the options to continue with shutdown (Yes) or abort (No).
- Sleep puts the computer in a suspended state, letting you quickly come right back to where you were working before you suspended the PC. This means you don't have to exit all your applications before turning off your computer. You only have to choose Sleep. This also saves energy because the hard drives, the CPU, the CPU fan, some internal electronics, and possibly the power supply and fan go into a low-power state. If your monitor is Energy Star compliant, it should also go into a frugal state of energy consumption. When you want to start up again, a quick press of the power switch (on some computers, a keypress on the keyboard or a jiggle of the mouse will do) should start up the system right where you left off.
- Be sure to press the power button for just a second or so. Anything more than 4 seconds on most modern computers in a Sleep state causes the computer to completely power down.
- Be aware that Sleep holds your system state only as long as the computer has power. In XP, if the power failed, everything stored in the computer's RAM is lost. You'd end up doing a cold boot when the power is restored or, if it's a laptop with a dead battery, when you hook up your AC adapter to your laptop again. The good news is that in Windows 7, Sleep is more intelligent. When the battery level gets too low, the power management system in Windows 7 switches into gear and initiates Hibernation (which we'll discuss next). One of the more interesting features of recent versions of Windows, including Windows 7, is hibernation. Like Sleep mode, hibernation lets you pause your work and resume later, without laboriously shutting down and reopening all your applications and files. But unlike Sleep, Hibernate isn't"volatile." If the AC power fails or batteries run flat, it doesn't matter because Hibernate stores the system state—that is, the contents of memory and the status of all hardware devices—on a portion of the hard disk, instead of keeping the system RAM alive in a low-power state. After storing the system state to the hard disk, the computer fully shuts down. When it's restarted, a little internal flag tells the boot loader that the system has been stored on disk, and it's reloaded into memory.
- Hibernation requires as much free hard disk space as you have RAM in your PC. If you have 512MB of RAM, you'll need 512MB of free disk space for hibernation to work. When you choose Hibernate from the Shut Down menu, Windows 7 has to create a fairly large file on disk. In my case, for example, it's 2GB in size. On a 3GHz Intel Pentium 4, the entire process takes about 15 seconds. Restarting takes about the same amount of time. Remember, if you're going to put a laptop running on batteries to sleep for more than a few hours, use Hibernate or just do a complete shutdown, closing your applications and documents. That way, if the batteries run out, you won't lose your work.