Internet Explorer | Firefox | Safari

By default, Safari doesn't come with the ability to export bookmarks.
You will need to enable the 'Debug' dropdown menu to export your bookmarks.

Here is how to do it:

Copy/Paste the following command in Terminal (Applications > Utilities) (while Safari is NOT running):
defaults write com.apple.Safari IncludeDebugMenu 1

If you wish to disable it open the Terminal and Copy/Paste this in: (while Safari is NOT running)
defaults write com.apple.Safari IncludeDebugMenu 0

This menu will give you the ability to import/export bookmarks.