There are different ways to reformat a computer, mostly depending on the operating system and how thorough the rewriting needs to be. Under most circumstances, no matter the system, a boot disc is necessary to reformat a computer. For Windows®, a user needs to press the F12 key when booting up, while Mac OS® users can use the Disk Utility. It is generally recommended to allocate several hours to reformatting a computer and reinstalling an operating system.
Using the original installation disc is the most typical way to reformat a computer running a version of Windows®. The computer should be restarted once the disc is placed in the drive. Pressing the F12 key prevents the computer from starting up normally and allows the user to tell the computer to boot from the installation disc instead of the hard drive. After the disc is selected as the boot device, the computer starts up and allows the user to reformat.
A list of partitions is displayed to the user once a computer boots from a Windows® installation disc. Most Windows® computers have one or two partitions; if the computer has two partitions, one is often much larger than the other. In this case, the small partition is usually a recovery or backup partition. It is only necessary to focus on the large partition while reformatting. The process is started using the arrow and enter keys after identifying the correct partition to reformat.
Computers running on Mac OS® can be reformatted by opening the Disk Utility, choosing a disk, and clicking “Erase.” To reformat the start-up disk, the computer must be booted with the Install Disk. Like with Windows® computers, important data should be backed up before proceeding. Unless the disk is to be used for something special, the default reformatting settings will usually work best.
Sometimes there are two options to reformat a computer running Mac OS®: high and low. A high-level reformatting is quick, usually less than a couple minutes, and designed for troubleshooting. Low-level reformatting can take much longer, but also erases all data rather than eventually rewriting the data as space becomes limited.
Reinstalling an operating system can take several hours. It can also take a significant amount of time to install important updates and favorite applications. If possible, it is best to set aside an entire day to ensure the computer is operational again when needed.