Answers...

to commonly asked questions.

How to Hide/Show all files on a Mac.

To show invisibles:

In terminal type the following:
defaults write com.apple.Finder AppleShowAllFiles YES

then killall Finder

to hide invisibles:

In terminal type the following:
defaults write com.apple.Finder AppleShowAllFiles FALSE

then killall Finder
This image is a theme.plist hack