In the default user interface, the property window is placed on a floating window. The general purpose property window is context sensitive; it adapts to the type of the selected objects. The select window's visible tab and the objects being selected in the tab together define what controls the property window includes.
There are also some 'sticky' versions of the property window available: they always show properties of selected objects for a certain object layer (independent of select window's tab selection). For example, the following windows which are all available in the 'Windows' pull down menu are such sticky property windows:
The property window has only one gadget that is common to all object classes: the Name gadget. You can rename one single object as well as several multi-selected objects using it. Remember to hit Tab or Enter key to confirm renaming before closing the property window.
The object property windows can also show properties of multi selected objects. If the values are different, the value of the first selected object is shown using red conflict color. Changing the value sets the same value to all selected objects (hence clearing the conflict state).
The object specific documentation about the property window can be found from the Models section of the reference manual.