|Microsoft Windows 1.x|
It was in development since at least 1983 and was originally named "Interface Manager". The name was later changed to "Windows" for marketing purposes. Several pre-release versions were released (some of which also leaked later), such as Development Releases 1-5, Alpha, and Beta.
A final preliminary release, Premiere Edition (1.00), was compiled on 17th August 1985, and subsequently released to a limited number of people (along with a later compile from August 20th that year, with some slight updates), and 1.01, released on November 20th, 1985, was the first version of Windows to be released to general availability (it was called Windows 1.01 to differentiate it from Windows Premiere Edition), whereas several more versions, Windows 1.02 and Windows 1.03, were released, as per smaller updates made to the code, with the latest version, 1.04, being released in April 1987.
Windows 1.0 was not widely successful, and was quite understandably pronounced as a "flop" by some people, though it was the start of Microsoft's entrance into the then growing graphical user interface-based operating system market.
Several copies in other languages, such as Windows 1.03 in German and French (and a hard drive image of Windows 1.03 Japanese for the PC-98), as well as certain OEM releases, such as a Zenith OEM release of Windows 1.01, and Olivetti and Siemens OEM releases of Windows 1.03, are known to exist.
DR5 is often mislabeled as DR3. Only DR5 is confirmed to exist, but because there is DR5, it's also logical there were DR1-4.
- Windows Developer Release 1 (DR1)
- Windows Developer Release 2 (DR2)
- Windows Developer Release 3 (DR3)
- Windows Developer Release 4 (DR4)
- Windows Developer Release 5 (DR5)
- Windows Alpha
- Windows Beta
- Windows Premiere Edition
- Windows 1.01 (Retail)
- Windows 1.02 (Retail)
- Windows 1.03 (Retail)
- Windows 1.03 (Olivetti OEM)
- Windows 1.03 (Siemens OEM)
- Windows 1.04 (Retail)