Following types exist:
This is the default type of windows and no special modes are set for this.
Desktop type windows are usually file managers that display icons and stay at the bottom of the window stack. They have no window title, no border and can neither be resized nor moved.
Dock type windows are usually panels that provide different kind of information and accessibility.
Toolbar windows are usually windows with either text or icons menu entries.
Splash windows are usually silly progress windows that are a placeholder until an app is ready.
Dialog windows are usually any kind of setting or message windows.
Following modes exist:
This mode disables the window border of the window and uses the additional space for the window.
This mode centers the window on the screen.
This mode enables the honoring of size hints, that are hints for the window manager about special size preferences and constraints like an aspect ratio.
This mode overrides the tagging and makes the window visible on all views on the same screen. When a window isn't normally visible on a certain view the current gravity instead of the default gravity will be used.
This mode spans a window across all screens regardless if the window is normally visible there.
This mode looses the window from the gravity grid and raises it above other windows. Size hints are automatically honored in floating mode and windows can be moved and resized. (Doing that with gravitated windows enables floating mode)