C# Definition:

    /// <summary>
    /// Enumerates the valid hook types passed as the idHook parameter into a call to SetWindowsHookEx.
    /// </summary>
    public enum HookType : int
    {
    /// <summary>
    /// Installs a hook procedure that monitors messages generated as a result of an input event in a dialog box,
    /// message box, menu, or scroll bar. For more information, see the MessageProc hook procedure.
    /// </summary>
    WH_MSGFILTER = -1,
    /// <summary>
    /// Installs a hook procedure that records input messages posted to the system message queue. This hook is
    /// useful for recording macros. For more information, see the JournalRecordProc hook procedure.
    /// </summary>
    WH_JOURNALRECORD = 0,
    /// <summary>
    /// Installs a hook procedure that posts messages previously recorded by a WH_JOURNALRECORD hook procedure.
    /// For more information, see the JournalPlaybackProc hook procedure.
    /// </summary>
    WH_JOURNALPLAYBACK = 1,
    /// <summary>
    /// Installs a hook procedure that monitors keystroke messages. For more information, see the KeyboardProc
    /// hook procedure.
    /// </summary>
    WH_KEYBOARD = 2,
    /// <summary>
    /// Installs a hook procedure that monitors messages posted to a message queue. For more information, see the
    /// GetMsgProc hook procedure.
    /// </summary>
    WH_GETMESSAGE = 3,
    /// <summary>
    /// Installs a hook procedure that monitors messages before the system sends them to the destination window
    /// procedure. For more information, see the CallWndProc hook procedure.
    /// </summary>
    WH_CALLWNDPROC = 4,
    /// <summary>
    /// Installs a hook procedure that receives notifications useful to a CBT application. For more information,
    /// see the CBTProc hook procedure.
    /// </summary>
    WH_CBT = 5,
    /// <summary>
    /// Installs a hook procedure that monitors messages generated as a result of an input event in a dialog box,
    /// message box, menu, or scroll bar. The hook procedure monitors these messages for all applications in the
    /// same desktop as the calling thread. For more information, see the SysMsgProc hook procedure.
    /// </summary>
    WH_SYSMSGFILTER = 6,
    /// <summary>
    /// Installs a hook procedure that monitors mouse messages. For more information, see the MouseProc hook
    /// procedure.
    /// </summary>
    WH_MOUSE = 7,
    /// <summary>
    ///
    /// </summary>
    WH_HARDWARE = 8,
    /// <summary>
    /// Installs a hook procedure useful for debugging other hook procedures. For more information, see the
    /// DebugProc hook procedure.
    /// </summary>
    WH_DEBUG = 9,
    /// <summary>
    /// Installs a hook procedure that receives notifications useful to shell applications. For more information,
    /// see the ShellProc hook procedure.
    /// </summary>
    WH_SHELL = 10,
    /// <summary>
    /// Installs a hook procedure that will be called when the application's foreground thread is about to become
    /// idle. This hook is useful for performing low priority tasks during idle time. For more information, see the
    /// ForegroundIdleProc hook procedure.
    /// </summary>
    WH_FOREGROUNDIDLE = 11,
    /// <summary>
    /// Installs a hook procedure that monitors messages after they have been processed by the destination window
    /// procedure. For more information, see the CallWndRetProc hook procedure.
    /// </summary>
    WH_CALLWNDPROCRET = 12,
    /// <summary>
    /// Installs a hook procedure that monitors low-level keyboard input events. For more information, see the
    /// LowLevelKeyboardProc hook procedure.
    /// </summary>
    WH_KEYBOARD_LL = 13,
    /// <summary>
    /// Installs a hook procedure that monitors low-level mouse input events. For more information, see the
    /// LowLevelMouseProc hook procedure.
    /// </summary>
    WH_MOUSE_LL = 14
    }

VB Definition:

Enum HookType as Integer
     WH_JOURNALRECORD = 0
     WH_JOURNALPLAYBACK = 1
     WH_KEYBOARD = 2
     WH_GETMESSAGE = 3
     WH_CALLWNDPROC = 4
     WH_CBT = 5
     WH_SYSMSGFILTER = 6
     WH_MOUSE = 7
     WH_HARDWARE = 8
     WH_DEBUG = 9
     WH_SHELL = 10
     WH_FOREGROUNDIDLE = 11
     WH_CALLWNDPROCRET = 12
     WH_KEYBOARD_LL = 13
     WH_MOUSE_LL = 14
End Enum