Last update: 2011/08/21
Interacting with computers is not straightforward. A brief history of how we moved from command line to the Graphical User Interface.
Devising methods to interact with machines and the very act of interacting with them are often endeavours with varying degrees of challenge. Playing a musical instrument may require years of practice, while setting the time on a mechanical wristwatch is rather straightforward. Doing the same on a digital wristwatch may not be straightforward while changing a program on a TV set is easy, even though setting the programs for the first time may be a challenge. For some reasons the act of programming the recording time on a Video Cassette Recorder (VCR) has achieved the status of emblem in user unfriendliness.
Early computers had extremely primitive forms of Human-Machine Interaction (HMI). The first peripherals attached to computers were those needed to input and output data, possibly in the form of programs: paper tape, card readers, teletypewriters and line printers. But more primitive forms of interaction were also used. To boot one of the early Digital Equipment PDP-11 minicomputers, still used at CSELT in the mid 1970s, required the manual introduction, through switches, of a basic sequence of binary instructions.
At that time interaction with computers had already considerably improved and was based on a very simple Command Line Interface (CLI). On the PDP-11, the RSX OS had a simple command line structure: a 3-letter code to indicate the function (e.g. PIP - Peripheral Interchange Program, to move files from one device to another) was followed by a sequence of characters specific to the particular function invoked with the first 3 letters. But with CPU power increasing in the 1960s and early 1970s, researchers began to consider new ways to reduce the time it took to enter data and reduce typing errors. The airline reservation systems, the earliest mainframe query protocols still in use, were developed during that period of time with the goal to stuff as much information as possible into compact command.
In the middle to late 1970s, the microcomputer caused a drop in price of computing power resulting in the popularisation of computing that later materialised in the PC. So research was started on the "next generation" of computers because moving interaction with computers from the "vestals" model recalled above, to the "anybody does what he likes with his PC" model, did require substantial changes.
The most notable interface research was carried out at the Xerox Palo Alto Research Center (PARC), where the first operational Alto computer, completed in 1973, was the first system equipped with all the elements of the modern Graphical User Interface (GUI): 3-button mouse, bit-mapped display and graphical windows.
The development of Alto was driven by the desire to provide a more effective HMI by making the computer communicate in ways more congenial to humans than possible before. Visual elements with a graphic content - icons - were introduced because they could be more effectively tracked by the part of the brain handling visual stimuli, unlike characters that represent a highly structured form of information potentially requiring sophisticated and highly specialised processing by the brain.
Eight years later (1981) Xerox introduced the Star, the commercial version of the Alto computer whose interface added the concept of the desktop metaphor, overlapping and resizable windows, double-clickable icons, dialog boxes and a monochrome display with a resolution of 1024*768, virtually everything that we see today on our PC monitor, save for colour. Xerox was unable to commercially exploit this innovative development.
Apple Computer was the one that really benefitted from the new HMI. Xerox allowed Apple to take elements of the Star interface in exchange for Apple stocks. The first computer with the new HMI - Lisa - was released in 1983 but flopped and was followed by the Macintosh the following year. The Macintosh turned out to be a success that continues to this day, through alternate phases. For several years Apple spent millions USD to enhance the Macintosh GUI, a commitment that paid off in the late 1980s when the professional market boomed and Apple's GUI became an emblem of the new world of personal computing, widely praised and adopted by artists, writers, and publishers. For some time in the early 1990s, Apple was the biggest PC manufacturer. The consistent implementation of user interfaces across applications can be mentioned as another reason for the success of the Macintosh.
Compared with what was brewing at Xerox and Apple, the IBM PC running MS-DOS had a cryptic Command Line Interface (CLI), but things were evolving. Already in 1983 some application programs like Visi On by Visi Corp, the company that had developed the epoch-marking Visicalc program, had already added an integrated graphical software environment. In 1984 Digital Research announced its GEM icon/desktop user interface for MS-DOS, with just two unmovable, non-resizable windows for file browsing, a crippled version of its original development.
In the second half of the 1980s, Microsoft embarked on the development of a new OS with a different GUI but for some time also cooperated with IBM in the development of their new OS, called OS/2, that IBM hoped would be generally adopted by the PC industry. Later, however, the partnership soured and Microsoft went it alone with Windows. At first the new interface was simply a special application program running on top of MS-DOS, which made available different graphic shells running on top of MS-DOS and providing such features as GUI and single-user multitasking. Apple sued Microsoft about the use of its GUI but Microsoft successfully resisted.
A similar process happened with UNIX. Like MS-DOS, UNIX has an obscure CLI inherited from mainframes. In the 1980s UNIX GUI shells were developed by consortia of workstation manufacturers to make their systems easier to use. The principal GUIs were Solaris by Sun Microsystems and Motif by Open Software Foundation (OSF).
With computers taking on many more forms than the traditional workstation or the PC, the HMI is becoming more and more crucial. One major case is provided by mobile handsets where the reduced size of the device puts more constraints on the ability of humans to interact with the range of new services that are in offer today. The hottest spot is the set of technologies that Apple has assembled for its iPod, iPhone and iPad devices. Other companies endeavour to emulate - and sometimes are brought to court.
It is now some 40 years since the GUI paradigm was first applied, and its use is now ubiquitous. There are new forms of interfacing, like interacting with services via telephone or devices like set top boxes by voice commands. A recent new area is communication with set top boxes or gamne machines via body movements.
