How can I see hidden files and folders in Finder?
By default, Finder does not display files and folder satisfying certain criteria, including all items having a name beginning with a dot, all items with the hidden flag set. To make these files visible in Finder, open Terminal.app and type the following command:
OS X 10.8 Mountain Lion and earlier:
defaults write com.apple.finder AppleShowAllFiles TRUE && killall Finder
OS X 10.9 Mavericks and later:
defaults write com.apple.finder AppleShowAllFiles -boolean true && killall Finder
Exception: this does not show Finder’s .DS_Store files where Finder stores certain folder properties such as icon positioning and size and view setting.
To make hidden files and folders hidden again, replace true by false in the above commands.
Starting with macOS 10.12 Sierra, you can also press ⌘⇧. (cmd-shift-dot) in Finder to turn the display of hidden files on or off.
Warning: That certain files are hidden in Finder usually has a reason: don’t fiddle around with these, because frequently these files are used by processes and applications to support correct operation. Prominent examples: ownCloud creates a hidden file called .owncloudsync.log in each folder being synched. macOS creates files called .localized in the default folders of a new user account holding the corresponding localized folder name.