, released on
November 20 1985 , was
Microsoft 's first attempt to implement a
Multi-tasking Graphical User Interface -based
Operating Environment on the
PC platform.
Unlike later versions, Windows 1.0 offered limited multitasking of existing MS-DOS programs and concentrated on creating an interaction
Paradigm , an execution model and a stable
API for
Native programs for the future. Due to Microsoft's extensive support for
Backward Compatibility , it is not only possible to execute Windows 1.0
Binary programs on current versions of Windows to a large extent, but also to recompile their
Source Code into an equally functional "modern" application with just limited modifications.
Windows 1.0 was often mistakenly regarded as a "front-end to the
MS-DOS Operating System ", a description which was also applied to subsequent versions of Windows. Indeed, Windows 1.0 was started from MS-DOS, Windows 1.0 programs could call MS-DOS functions, and GUI programs were run from
.exe files just like MS-DOS programs. However, Windows .exe files had their own "new executable" (NE) file format, which only Windows could process and which for example allowed demand-loading of code and data. Applications were supposed to handle memory only through Windows' own memory management system, which implemented a software-based
Virtual Memory scheme allowing for applications larger than available
RAM .
The treatment of Windows 1.0 as a "DOS front-end" fails to take into consideration that it was designed to be just a graphics environment used by applications, rather than a full-fledged operating system. Windows 1.0 included original
Device Driver s for video cards, mice, keyboards, printers and serial communications. Applications were supposed to only invoke APIs built upon these drivers. Given that contemporary graphics support in MS-DOS was extremely limited and given the limited usefulness of the other services, MS-DOS applications had to go to the ''bare hardware'' (or sometimes just to the
BIOS ) to get work done. Therefore, rather than being a front-end to MS-DOS, Windows 1.0 complemented and partially replaced it. The level of replacement would increase in subsequent versions.
The first release version was actually numbered 1.01. However, it is rumored that version 1.00 was actually released but quickly pulled due to a severe flaw. There were also experimental versions that got out, such as the 0.9 beta.
Version 1.02, released in May
1986 was international and had editions in several European languages.
Version 1.03, released in August 1986, was US-only, with enhancements making it consistent with the international release. It included drivers for European keyboards and additional screen and printer drivers.
Version 1.04, released in April
1987 , added support for the
VGA graphics adapters of the new IBM
PS/2 computers. At the same time Microsoft and IBM announced the introduction of
OS/2 and its graphical OS/2
Presentation Manager , which were supposed to ultimately replace ''both'' MS-DOS and Windows.
Windows 1.0''x'' was superseded in November 1987, with the release of
Windows 2.0 .
The system requirements for Windows 1.0 constituted MS-DOS 2.0, 256 KB RAM, and 2 double-sided disk drives or a hard drive.
This first version of Windows ran a
Shell program known as MS-DOS Executive. Other supplied programs were
Calculator ,
Calendar ,
Cardfile ,
Clipboard viewer,
Clock ,
Control Panel ,
Notepad ,
Paint ,
Reversi ,
Terminal ,
Write , and the
Command Prompt .
One of the interesting aspects of the system were the non-overlapping windows, which were instead ''tiled''. Only dialog boxes could appear over other windows.
Windows 1.0 executables, while having the same .exe
Extension and initial file header as
MS-DOS programs, did not yet contain the so-called ''MS-DOS stub'' which prints the "This program requires Microsoft Windows" message and exits when the program is run outside of Windows. Instead, the file header was formatted in such a way as to make DOS reject the executable with a "program too large to fit in memory" error message.
From the beginning, Windows was intended to multitask programs (although this originally only applied to native applications and for many versions the multitasking was
Non-preemptive ), so Windows programs always had their own
Menu Bar rather than switching a single menu bar at the top of the screen like
Apple Macintoshes did.
Originally Windows was designed to have the pull-up menus at the bottom of windows, as it was common with the DOS programs of the time; however, this was changed before the first release.
The history of Windows dates back to probably did not help the sales of
VisiCorp 's
Visi On environment which debuted at the same time. However, even when finally released, Windows 1.0 aroused little interest as well, showing the market was simply not yet ready for a switch-over from MS-DOS.
Another GUI for the PC platform at the time was
GEM . It had a nicer look, notably because it copied more aspects from the
Macintosh GUI , for example the
Trash Can concept (which Microsoft would in turn copy in future windows releases) and more generally the desktop interaction. GEM was eventually used as the standard GUI for the Atari's
ST range of
68k -based computers, which were sometimes referred to as
Jackintosh es as a slurry of thought (the company being run by
Jack Tramiel ). GEM's resemblance to the Macintosh OS later caused legal trouble to the manufacturer,
Digital Research , who were obliged to seriously cripple the desktop's appearance and functionality (applications were not affected).
But GEM was not multitasking, so users had to close one program in order to run another one. Collections of related programs, like
GEM Draw , had tricky File menu items like ''Close (to Edit)'' to facilitate switching.
An alternative multitasker released shortly before was
DESQview , a successor of
IBM 's failed
TopView from
1984 . It did not have graphical capabilities initially, but was able to multitask DOS applications in windows as long as they were well-behaved or had a specially written "loader" which could fix them on the fly.
As the result of this heavy competition, Windows gained very little market share – until
Aldus PageMaker shipped in
January 1987 with a Windows executable. This was the first
WYSIWYG Desktop Publishing program available on the PC platform, and it finally gave people a reason to buy Windows. Later Windows compatible products included
Excel and
Corel Draw .
