For many years, Macs have relied on sets of keys held at startup to enable specific modes. Most notably, pressing Option displays the Startup Manager and lets you pick a boot drive, Command-R starts up from macOS Recovery, Command-Option-P-R resets the NVRAM, Shift starts up in Safe mode, D opens Apple Diagnostics to check the hardware, and T starts up in Target Disk Mode. Needless to say, obsc... Read more