WinShell is a graphical user interface for working with LaTeX or TeX. It includes a text editor, different toolbars and user configuration options. It is not a TeX-system---you need an additional TeX package for DOS/MS-Windows (e.g., miktex or fptex). For previewing documents you will need something like GhostScript or dviwin. The author is Ingo H. de Boer. See also texniccenter texshell32 winedt.