In April 1987 Microsoft shipped Windows 2.x, a graphical shell that ran atop MS‑DOS while IBM developed OS/2. Both environments shared a remarkably similar UI, a deliberate move to let Windows users migrate to OS/2 without relearning basics. The release added desktop icons, keyboard shortcuts, and overlapping windows that Windows 1.x lacked. It ran on 8086/8088 hardware even as 286 and 386 chips emerged.

Pressure fell on Tandy Trower, who returned after rescuing Windows 1.x, and on a design team that hired graphic artists instead of programmers. Within eight months they implemented proportional fonts, true overlapping windows, and a memory‑management trick that tapped extended RAM beyond the 640 KB conventional limit, a technique also used by Lotus 1‑2‑3. These UI choices echoed the Lisa and Macintosh efforts, influencing products through 1990s.

Microsoft marketed Windows 2.x as a stopgap while OS/2 matured; the two products shared a roadmap negotiated by Steve Ballmer. Apple sued both firms in 1988, claiming Windows copied the Macintosh “look and feel,” a claim complicated by an earlier royalty‑free license for Windows 1.x. Ultimately Windows 2.x proved the more successful branch, shaping GUIs. The Windows/286 and Windows/386 variants appeared, cementing Microsoft's foothold in the PC GUI market.