Title says it all really.

You’d usually have to drop down into a terminal to manipulate Unix-style ‘.’ hidden folders, which isn’t a problem to me. However, it becomes a hassle when you want to place something from let’s say a browser save, into one of these hidden folders, via a Finder window (because I don’t want to have to do a ‘mv’ later in the terminal). Well youcan display those hidden files and directories with this [terminal] command:

defaults write com.apple.finder AppleShowAllFiles -bool true

Once I’d done that, I needed to restart Finder, which is done,simply, via the Apple menu’s ‘Force Quit’ option (it doesn’t actually allow you to quit Finder, the button changes to ‘restart’). I’ve attached a screen shot to outline this.

I’m guessing that to reverse this, you only need to set the above to false (I’m reasonably sure of that, I just haven’t tried it yet myself).