It is oh-so-tempting to just pull that flash drive out of your USB port when you’re done with it. But resist the urge! Unceremoniously disconnecting an external drive from your Mac can result in all sorts of problems—namely, you could inadvertently damage files on the drive. Do yourself—and your data—a favor and eject your disk the proper way. OS X provides a few methods for doing so—here are three of them.
Dragging the icon: This method of ejecting a disk has been around as long as the Mac itself. Click the disk icon on the desktop (assuming you have your Mac set to show disks on the desktop), then drag it to the Trash icon in the Dock—it’ll turn into an Eject symbol. Wait a few seconds for the disk to disappear from the desktop and remove your disk.
From the keyboard: If you have a Mac with an optical (CD or DVD) drive, you can easily eject CDs or DVDs: Simply hold down the Eject key in the upper right corner of your keyboard until your Mac spits the disc out. This only works for optical drives, though—something Apple doesn’t even include on its current hardware.
From a Finder window: Pop open a Finder window, and look for the disk you want to eject under the Devices subheading. (If removable disks like flash drives aren’t showing in your Finder sidebar for some reason, select Preferences… from the Finder menu, click Sidebar, then check the boxes for External disks and CDs, DVDs, and iPods.) Click the Eject symbol next to the disk you want to eject, wait for the disk to disappear from the sidebar, then go ahead and disconnect it.
What if a disk won’t eject?
If you have any file stored on a disk open in any app, OS X may prevent you from ejecting a disk so you don’t mess up any of your data. If this happens, close the file in question and try again. In some cases, OS X will allow you to “force-eject” a disk, but you may still lose data, so force-eject wisely.