Floaters are small spots on the screen which provide convenient access to gestures using a touchscreen or pen.
The standard floater can be displayed by right-clicking the tray icon and selecting Toggle Floater. Double-tap the main floater to show the Control, Alt, and Shift floaters. Double-tap a secondary floater to toggle the modifier on or off. Triple-tap the main floater to open the context menu, long-press and hold (longer than Cancel Delay) to drag the floater to a different area of the screen.
When you draw from the main floater, it acts the same as holding the primary stroke button and drawing a gesture. Drawing a line from the Control floater is the same as pressing the Control key and drawing with the standard stroke button.