I recently switched over from PC to Mac and when I was looking through my folders I realized some things were missing. The folders missing all were named with a period coming before the name. The purpose was for them to arrange themselves at the top when folders are arranged alphabetically. However, on a Mac, in OS X a period before the name means that it becomes a hidden folder / file.
Below is the command to show the hidden files in the Mac OS X Finder.

Open up the terminal and type the following commands:

defaults write com.apple.finder AppleShowAllFiles TRUE
killall Finder

Also, to revert back to normal, here is the command:

defaults write com.apple.finder AppleShowAllFiles FALSE
killall Finder