[4] It provides developers the ability to create GUI widgets using the Tk toolkit and the Tcl programming language.
[5][6] wish is open-source under the BSD License, and is currently part of the Tcl/Tk programming suite.
Then the % prompt is displayed and the interpreter awaits for commands entered interactively by the user.
An empty window is opened in which the widgets created by user commands are displayed.
It is also possible to run directly Tcl/Tk scripts; in Unix using the shebang construction; in Windows by associating the .tcl extension with the wish program.