How you end a computer session depends on how you use the computer, your views on energy conservation , and what you have been told about how your decision will affect your investment's longevity: will frequent starting and stopping cause its circuits  to burn out sooner? Rest easy, your computer is more likely to be damaged by a virus picked up from the Internet than by being turned off and on too much. They are also energyefficient: such efficiency has reached the point where most computers place themselves in sleep mode if they remain idle  for a certain period of time. So your computer will likely slip into sleep mode anyway, even if you leave it on overnight. Sleep mode itself, once a pretty unreliable option--you never knew if you would be able to wake your computer without having to reboot   it--has been vastly improved with newer operating systems. If you want your computer to consume as little energy as possible when not in use, shut it down. If you want it to consume zero energy, you're going to have to unplug (......) it. Your computer can be in only three states: on, sleep or off--each of which draws some level of electric current. A computer that is "on" will either be actively processing  information or sitting idle, depending on whether the user is typing a document, reading an email or has stepped away briefly. The amount of wattage   drawn when the computer is on varies greatly depending on whether it is a laptop or a desktop computer. The latter uses more energy because desktop power supplies are less efficient and require a separate and often larger, powerhungry monitor. It also varies based on the type of work being done: complex calculations requiring intensive processing are more powerhungry, whereas writing or Web browsing consumes far less electricity. The reason why a desktop computer uses more energy than a laptop computer is that  _  .
a desktop computer's monitor is separate and often larger a desktop computer is larger than a laptop computer in size a desktop computer performs more kinds of work than a laptop computer a desktop computer is not energyefficient