Before Parallels and VMware Fusion had enough speed to make them practical for everyday use, many Mac owners used Apple's Boot Camp to run Windows on Mac hardware. There was even a time when some users claimed that the best Windows laptop was a MacBook Pro with Windows running under Boot Camp. Those days are long gone. Apple still officially supports Boot Camp, but it gets more awkward to use every year. A few years ago, when all Macs used the older HPFS file system, you could switch back from a Boot Camp-based Windows system to the operating system simply by clicking on an icon in a Mac-style Startup Disk applet accessible from the Windows taskbar. Now that all current Macs use the new APFS file system, the Startup Disk applet no longer works, because Apple didn't bother to update it to communicate with APFS drives. To switch back from Boot Camp-based Windows to the macOS, you have to hold down the Option key when restarting the Mac and then select your Mac drive as the startup disk. If your timing is wrong, you'll end up back in Windows. Apple seems to have decided that Parallels Desktop and VMware Fusion make Boot Camp irrelevant, but many gamers will still want Boot Camp because Parallels and VMware support DirectX graphics only through DirectX 10, while Boot Camp supports DirectX 11 and 12 if the graphics hardware on your Mac natively supports those DirectX versions.