The Simple Translator widget provides you the environment that you need to make short translations right from your Dashboard.
To install the Simple Translator widget, when the download is complete, unarchive it and place it in /Library/Widgets/ in your home folder. Show Dashboard, click the Plus sign to display the Widget Bar and click the widget’s icon in the Widget Bar to open it.
To learn more about dealing with the Mac OS X Dashboard you can easily access the Apple support page HERE.