Windows 1.0

operating system

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Last updated

July 22, 2026

Quick Summary

Windows 1.0, released on November 20, 1985, was the first version of Microsoft's graphical operating system (OS). Unlike later versions, it featured "tiling" windows, meaning they could not overlap on the screen, with only minor exceptions for pop-up windows. This early version was somewhat successful but not particularly memorable. It laid the groundwork for future iterations of Windows, which would eventually become the dominant OS worldwide. Windows 1.0 did not support applications like Microsoft Word or Excel, which were introduced in later versions.12

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list of Windows versions
Windows 1.0
The very first Windows version was somewhat successful but nothing especially memorable. Unlike other Windows versions, the software supported “tiling,” which did not allow windows to overlap on users’ screens. (Minor exceptions existed, such as for pop-up windows.)
Read More
The very first Windows version was somewhat successful but nothing especially memorable. Unlike other Windows versions, the software supported “tiling,” which did not allow windows to overlap on users’ screens. (Minor exceptions existed, such as for pop-up windows.)
Read More