In the Windows 7 OS...
Click the Start menu button on the task bar, then 'Lock' menu button
A hard boot, or cold boot, involves turning on the power with the on/off switch, A soft boot, or warm boot, involves using the operating system to reboot.
snow boot
A cold boot refers to starting a computer that has been powered off. A warm boot is just restarting Windows.
Unless you have to, it is many times advantageous to œwarm boot, or rather warm reboot, Windows . In a warm reboot, Windows restarts, but the computer doesnt, skipping the whole pre-Windows boot scree/BIOS/startup sequence. You an easily specify a warm boot in both Windows XP and Windows Vista. Just hold down SHIFT on your keyboard before clicking œRestart in Vista, or before clicking OK in the restart dialog in XP. Enjoy the extra 20 seconds!
A cold boot is done by completely powering down the computer to off and then starting the computer fresh. A warm boot is restarting the computer without powering the computer off.
If you restart it in the menu with the mouse or keyboard then it's a "Soft" or normal reboot. If you have to restart with the power button (or restart button on older Macs) on the side of computer case then its a "Hard" reboot.
warm booting
Warm boot: not all the processes shut down. It does not take as long for a warm boot and many times users do not have to be off the system. Cold boot: Everything shuts down. There are shutdown scripts which shut down all the processes (so nothing is missed). All users must be off the system. Then, you run the startup script (check for errors). Test the system to make sure the changes you made took effect and there's no problems. Warm boot example: Configurable parameter was changed and the documentation states in order for it to take effect, a warm boot is required. In the documentation for that particular system, a warm boot's criteria will be listed. Cold boot example: Operating system upgrade on the server.
A warm boot is faster than a cold boot because it restarts the computer without turning off the power, allowing the system to bypass certain hardware checks and initialization processes. In a warm boot, the operating system can quickly reload from memory, while a cold boot requires the system to perform a full hardware initialization and load the operating system from scratch. This reduction in startup processes makes warm boots significantly quicker.
A cold boot always begins with the power off whereas a warm boot does not interrupt the power supply. Although there may not appear to be any difference on the surface (a POST is performed regardless), a cold boot is more reliable as it ensures all hardware is properly reset. When diagnosing hardware issues, it's always best to cold boot the system to ensure consistency. It's also best to let the system rest for at least 30 seconds to allow any residual current to drain before powering up again. Ideally, external peripherals (USB drives, printers, domestic routers, etc) should be turned off as well. Hardware issues are problematic enough without increasing the number of variables you have to contend with.
A Warm Boot
If the computer is off the boot is called a cold boot or initial startup.If the computer is on the boot is called a warm boot or restart.