Unfortunately, the idiom’s success and utility have given many designers the wrong idea: They believe that replacing more common imperative controls such as buttons or butcons with underlined words will automatically result in a more usable and successful user interface.
Right-clicking on an underlined word pops open a menu of possible alternatives to choose from.
What do the underlined words "cordierite, calcite or tourmaline" mean?
If a user is interested in an underlined word, she may click on it and will be brought to a new page with more information.