Winndiff

Windiff (often stylized as WinDiff) was introduced by Microsoft not as a standalone commercial product, but as a utility within the and later bundled with development tools like Visual Studio. Its primary purpose was to provide a visual representation of file differences to system administrators and developers who needed to troubleshoot system changes, compare configuration files, or verify code deployments.

Before graphical diff tools became standard, comparing files was a text-based affair. Tools like diff on Unix or fc (File Compare) on DOS required the user to parse cryptic outputs, mentally visualizing how lines were added, removed, or changed. winndiff