If your Mac is sick, the first step is to restart it. But did you know that there are several tricks you can perform while your Mac is starting up?
Many of these are advanced Mac diagnostic tools, which shouldn’t be used unless you really know what you’re doing. But some not-so-secret startup keyboard combos will remove a stuck disk (if your Mac is old enough to even have a disk inside), let you boot your Mac from a USB drive, or to turn your entire computer into one big storage disk to connect to another computer.