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 web2c-win32). For previewing documents you will need something like GhostScript or dviwin. This package was implemented by Ingo H. de Boer. See also texshell32 winedt fourtex miktex web2c-win32 ghostscript.