Windows, DOS and the Mac. (Personal Computing) (column)

Windows, DOS, and the Mac Direct-manipulation or graphical user interfaces (GUIs) are nearly as old as command-line interfaces. (1) At the ACM Conference on The History of Personal Workstations, Doug Ross told of drawing on an oscilloscope screen by using his finger to move a spot of light in 1954. Graphic software has been a bastion of direct manipulation since the 1950s, and Douglas Englebart demonstrated direct manipulation of text to large audiences in the 1960s. The style of contemporary direct-manipulation interfaces evolved largely from prototypes developed at the Xerox Palo Alto Research Center (PARC) in the 1970s. The Xerox Star offered a commercial GUI in 1981 (see Figure 1), and several early GUIs, like VisiOn, TopView, and Windows version 1, failed on underpowered PCs. The Macintosh, introduced in 1984, was a major commercial success.

Although GUIs have been used for years, the hardware to support them is expensive, so the vast majority of personal computer users still control their software by typing commands. With the introduction of Windows Version 3, Microsoft hopes to move DOS users away from their command-line interface to a direct-manipulation interface. Let us take a quick look at Windows, then compare it to DOS and the Mac.

Windows 3

Windows was announced on May 22 1990, but beta copies had been circulating for months prior to the announcement. Microsoft stated that the $10 million they spent on the multicity, multimedia rollout and advertising campaign was an industry record. I must admit that the hype worked its magic on me. It also worked on Wall Street and with potential customers. Between April 25 and May 22, Microsoft stock rose from 55-5/8 to 78-3/4, gaining over 40 percent, and Jeffrey Tartar, publisher of Softletter, a software industry newsletter, predicts sales of as many as six to nine million copies of Windows during its first year. (2)

The most visible part of Windows is the user interface. Figure 2 shows an application window. The scrollbars, menu bar, and other widgets are variations on a now familiar theme. If you have been using a Mac, GEM, Open Look, NeXT, or other similar systems, you will be able to use Windows' application interface with little or no reference to the manual.

Windows users will enjoy the interface uniformity the Mac is known for. For example, the File menu shown in Figure 2 would be similar in all applications, and located on the left, and a familiar Edit menu should be next to it. The Help menu should always be at the end of the menu bar, and it evokes a standard search and browse system, which if used well by developers, will be a significant addition to applications.

Most interaction with the operating system, as opposed to an application, is through the Program Manager, the File Manager, and the Task List. Let us look briefly at each of these.

The Program Manager in Figure 3 contains application groups, represented as icons within the Program Manager window. A group contains icons for one or more programs and data files. A typical group would contain icons for the files and programs used in a given project or activity. A group icon opens into a window when it is double clicked, and programs may be launched by double clicking their icons or the icons of files they created (assuming that the proper links have been established). Applications and files can be moved or copied from group to group by dragging their icons; however, they may not be nested--a group cannot contain another group. When a program is active, but not being interacted with, it can be minimized to an icon on the desktop. The two icons below the Program Manager window in Figure 3 represent such programs.

The File Manager is shown in Figure 4. It is typical of the tree-structured file browsers found in DOS 4.0 and many commercial and public domain utility programs. Most of the standard DOS file manipulation commands such as copy and erase are available by direct manipulation, and there are some new onces, for example move. The most glaring omission is the type command, which displays the contents of a file. To view the contents of a file, you must execute Note-pad, one of the application programs bundled with Windows.

Applications can be …