Many a times while installing some softwares or updating something, you are frequently asked to restart your system. In such cases, you can avoid restarting the Computer altogether from the BIOS and save your time.
When you click on the SHUTDOWN button, make sure to simultaneous press "SHIFT" Button. If you hold the Shift key down while clicking on SHUTDOWN button, you computer would restart without restarting the Computer. This is equivalent to term "HOT REBOOT".