WinHelp is a help file format (.hlp) created by Microsoft.
WinHelp (.hlp) was the successor of QuickHelp and was used in Windows 3.0 up to Windows 95 and NT.
The file format itself is based on RTF. WinHelp files generally consist of texts, pictures and macros in VBA language. The navigation in WinHelp 1.0 was only by means of hyperlinks, and a search dialog with index and full-text search (search) tab is possible. There is no table of contents - the "contents" button in the toolbar simply resulted in the main navigation topic in the help.
With the introduction of Windows Vista, support for WinHelp was abandoned, later as an additional update again optionally implemented for compatibility reasons. Windows 7 support is missing by default also.