There are two types of bindings, you can either bind actions to the mouse or to the keyboard. To understand how these work, lets first look how a typical screen with one Window and two Iconified Windows is set up. In the figure below notice how the screen is divided up into the following parts: R - the root window, I - Icon, F - frame corners, S - frame sides, T - title bar, W - application window and 0-9 - buttons. Note that A will stand for anywhere, i.e. it doesn't matter where the mouse is located.

Bindings are set up as follows, you can either bind a key to an action by 'Key X Context Modifier Action' or bind the mouse to an action 'Mouse X Context Modifier Action'. Context is where the mouse is currently located (as shown above) and the Modifier is any combination of the following; (A)ny, (C)ontrol, (S)hift, (M)eta, (N)othing, or 1-5, representing the X Modifiers mod1-mod5 (man xmodmap). Examples of bindings are as follows:

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# Basic Bindings
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Key F1 A M Menu MenuFvwmRoot
Key Tab A M WindowList Root c c NoDeskSort, SelectOnRelease Meta_L
Key Super_L A A FvwmATerm
Mouse 1 R A Menu FvwmRootMenu
Mouse 3 R A Menu FvwmWindowOpsMenu
Mouse 1 1 A FvwmDeleteOrDestroy
Mouse 1 3 A FvwmIconifyOrShade
Mouse 1 5 A FvwmMaximize 100 100
Mouse 2 5 A FvwmMaximize 0 100
Mouse 3 5 A FvwmMaximize 100 0
Mouse 1 W M FvwmMoveOrIconify
Mouse 1 I A FvwmMoveOrIconify
Mouse 4 T A FvwmWindowShade True
Mouse 5 T A FvwmWindowShade False

The bindings from order of top to bottom perform the following actions;

1. Opens the root menu when alt-f1 is pressed anywhere.
2. Opens the WindowList which lists the running applications when alt-tab is pushed, and then switches to the application you selected when the alt key is released.
3. Launches an aterm when the left command key (windows key) his hit.
4. Opens the root menu when the left mouse button is clicked in the root window.
5. Opens the window ops menu when the right mouse button is clicked in the root window.
6. Deletes or Destroys the window when button number 1 is clicked or double clicked.
7. Iconifies or Shades the window when button number 3 is clicked or double clicked.
8. Maximizes the window to fit the full screen when the first mouse button is clicked on button number 5.
9. Maximizes the window vertically when the second mouse button is clicked on button number 5.
10. Maximizes the window horizontally when the third mouse button is clicked on button number 5.
11. Moves the window with alt+click when the mouse moves and Iconifies the window a double click.
12. Binds the FvwmMoveOrIconify function to work on 'Icons' so they can be moved and UnIconified.
13. Shades the active window when you roll up on the mouse wheel twice, since the function requires a double click.
14. UnShades the active window when you roll down on the mouse wheel twice.