Copyright applies to the form of expression, not to the ideas expressed. When applied to programs, this means that the source and object code (i.e., program instructions written by the programmer) are protected by copyright, but not the algorithms which the code expresses. What about other expressive aspects of the program, such as the menus, commands, keystrokes, etc., by which the user controls the program, and the displays, windows, etc., by which the program presents information to the user? These aspects of a program are called the user interface---the place where the user and the program interact. The "look and feel" of a program derives from its user interface.
Can a user interface, or the look and feel of a program, be protected by copyright? Copyright law has been in a very confusing, unsettled state regarding this issue.
Prior to about 1990, software developers felt free to copy the user interface of other programs (but not, of course, the programs' code). In 1990, Lotus Development Corporation began winning lawsuits against Paperback Software and Borland International, Inc., for copying the user interface of its spreadsheet program, Lotus 1-2-3. Apple Computer, Xerox Corporation, and other companies have filed similar suits.
Some companies even claim to have copyrighted programming languages. In the Borland case, the U. S. District Court of Massachusetts ruled that the hierarchy of menus used in Lotus 1-2-3's user interface was protectable expression under the copyright law, because Borland could have renamed the menu commands---for example, by changing "Quit" to "Exit" and "Copy" to "Duplicate." In March, 1995, the U. S. Appeals Court (First Circuit) reversed this decision, holding that the menu command hierarchy is a method of operating the program; methods of operation are specifically excluded from copyright protection, under Section 102 (b) of the United States copyright law. (The Appeals Court did not rule on whether other aspects of the user interface, such as the screen displays and the help prompts, were copyrightable.) Lotus appealed the case to the Supreme Court, which recently (Jan/Feb '96) upheld the decision of the Appeals Court; i.e., Lotus lost, the Lotus menu command hierarchy is not copyrightable.
In our opinion, the decision made by the Appeals Court and the Supreme Court was wise: any monopoly (such as copyright) over a method of operation could have horrible consequences for users. Imagine, for example, that the first car manufacturer had a copyright over the automobile user interface that we're accustomed to today. Then other car manufacturers would either have to license the interface (if the first manufacturer would let them!) or invent a different interface. This would probably result in the development of dozens of incompatible interfaces for operating automobiles---some with steering wheels, some with sticks to control direction; some with brake pedals, some with hand levers for brakes. Imagine the confusion you would have if you tried to drive a different kind of car! Imagine the confusion there would be if every typewriter manufacturer used a different arrangement of the keyboard---which is nothing more than a menu of letters!
The situation is similar for computer users. If a new and better method of operating a computer program can be thought up, then that method should be available for all programs. Of course, the developer of the method should be adequately rewarded, but usually these rewards come from the sale of the first program to have this method of operation. Copyright law must balance the objectives of encouraging innovation, preserving competition, and rewarding the labor of authors; but the good of the public must come first, and this seems to require the free copying of methods of operation. On the other hand, some aspects of user interfaces, such as the phrasing of a help message and the layout of information displays, may be expressive, not operational, and as such would deserve copyright protection. (Note that the Appeals Court made no decision about any non-operational aspects of user interfaces.)