If you’re unsure check with a Mac expert or hire a Mac consultant. Some of them are critical files, so don’t throw away any invisible file without being sure that you have a full, bootable backup of your Mac and you know what you’re doing. These invisible files and folders are part of the Mac operating system, Mac OS X. Over the years, I’ve seen several hard drives that were filled with spurious log files or errant backup copies of data - all of which happened to be invisible. OmniDiskSweeper conveniently shows all the invisible files and folders on your Mac. If your hard drive is this full, please download and use OmniDiskSweeper to help you clean it up. I should be clear to mention that when the hard drive is nearly full, typically starting around 90%, the computer’s performance is significantly affected. Unless the hard drive is over 90% full, the computer’s performance is not affected by the amount of information stored there. People often erroneously think that their Mac is running slowly because the Mac’s internal hard drive has so much stuff on it. This helps you to focus your clean-up efforts on the folders that are taking up the most room on your Mac’s hard drive. OmniDiskSweeper will scan all files and folders on your Mac and list them by size, starting with the folders taking up the most space. Do you want to clean up your Mac hard drive? Is your hard drive nearly full and you don’t know why? OmniDiskSweeper (free) can help with both of these situations.

How to clean up mac computer hard drive