The next UI breakthrough: command lines

Once upon a time, computers were controlled by commands. The interaction paradigm was based on a control language; users entered commands and respective arguments on the line following the (invariably) blinking cursor. Then graphical user interfaces (GUI) appeared, replacing arbitrary memorized commands with direct manipulation, where actions are performed by moving objects on the screen and selecting from menu displays. GUI has served us well, replacing the need to memorize geeky instructions with the ease of selecting from the visible items on the screen. But GUIs work well only when the number of alternative items or actions is small. When the number of items reaches the level typical of today’s complex operating systems, applications, and the information spaces of the Internet, the GUI does not scale well. Even searching one’s email records is tedious with a GUI, and when it comes to photographs and music, it’s extremely difficult. The Internet, of course, cannot be navigated using just the visible structure. What is to replace the GUI? Ah yes, journalists are constantly asking me that question, hoping I will speak of virtual reality implants by which we fly effortlessly through hyperspaces, finding just the items of interest, then immediately packaging and caressing them to do our bidding in reports, diagrams, and instant insights of wisdom. Well, the answer is much simpler, and it’s already here: search. The real surprise, though, is that search engines have evolved into answer engines, controlled through a modern form of command line interface. We navigate the Internet by typing phrases into our browsers and invoking our favorite search engine. But more and more, we type in commands, not search items. All the major search engines now allow typed commands, bypassing any intermediate Web pages to directly yield answers. Consider these three examples, each for a different search engine.