Shut down with power button
People are still used to a forced shut down using the power button, when windows would hang. Years ago, using the power button under any circumstances was nearly equivalent to a power failure, causing a "dirty" shut down - I.e. where files and programs were not closed in an orderly manner before the system shut down. (Even today, you can force it down by holding the power button until it stops.). This could cause file and program damage, possibly even preventing the system from booting again.
Many IT Deartments instructed their users to NEVER shut down using the power button. In fact, doing so was likely the single most common reason for system failures, when users got impatient and shut down systems this way during Microsoft Updates to the O/S!
For some time now, however, systems have been configurable for what they do when the power button is briefly pressed. I believe that on many laptops, vendors have set this to put the computer in a sleep or suspended state. Most desktops probably come with this configured to shut down in an orderly fashion. BUT truth is you can still Force a shut down by pressing and holding the power button, and unless the system is truly "hung", its still not a good idea.
Before using the power button to shut down, be sure you know what the power button is configured to do (power off, suspend, or sleep), and make sure you know the difference between pressing the power button briefly, and holding it down.
