place window option value ?option value ...?
place configure window ?option? ?value option value ...?
place forget window
place info window
place slaves window
place window option value ?option value ...?
Arrange for the placer to manage the geometry of a slave whose pathName is window. The remaining arguments consist of one or more option-value pairs that specify the way in which window 's geometry is managed. Option may have any of the values accepted by the place configure command.
place is the most beautiful & flexible of the Geometry managers supported by Tk. It provides support for fixed or "rubber-sheet" placement of widgets.
http://www.purl.org/tcl/home/man/tcl8.4/TkCmd/place.html
[Any examples of how to use it, or tips on things to do or not do?]
See also:
Category Command - Tk syntax help - Arts and Crafts of Tcl-Tk Programming - Geometry Managers