oTab            - tabbed dialog (property sheet) class
 Stack           - generic stack of any size
 T_Error         - TopClass version of Error
 T_Get           - TopClass version of Get
 T_TBColumn      - TopClass version of TBColumn
 T_TBrowse       - TopClass version of TBrowse
 WAppBase        - application base class
     WApp            - SDI application
     WMDIApp         - MDI application
 WBColumn        - WBrowse column
 WBrowse         - WBrowse browser (grid)
 WHelp           - help information
 WMenuBase       - menu base class
     WMenu           - (bar) menu
     WPopup          - popup (drop-down) menu
     WSystemMenu     - system (control box) menu
 WMenuItem       - menu item
 WODBC           - ODBC
 WTable          - table (Xbase "database")
     WDBTable        - data-independent table
 WWindowBase     - window base class
     WControlWindow  - control base class
         WArrowButton    - button with an up/down/left/right arrow
         WBitmap         - bitmap control from a resource
             WBitmapStretch  - auto-sized resource bitmap control
         WBitmapFile     - bitmap control from a file
             WBitmapFStretch - auto-sized bitmap control from a file
         WBListBox       - browse using a list box (also inherits WBrowse)
         WButtonBitmap   - button displaying bitmap(s)
         WCheckBox       - check box
         WComboBox       - combo box
         WEdit           - edit control (input field)
             WGet            - an edit control with a picture
             WMLEdit         - multi-line version of WEdit
         WGroupBox       - group box
         WListBox        - list box
         WProgressBar    - progress bar
         WPushButton     - (push) button
         WRadioButton    - radio button
         WScrollBar      - scroll bar base class
             WHorizScrollBar - horizontal scroll bar
             WVertScrollBar  - vertical scroll bar
         WSpinButton     - up/down counter
         WTextControl    - text ("static" or @ SAY) control
             WCenterText     - centred text
             WLeftText       - left-aligned text
             WRightText      - right-aligned text
             WSSControl      - generic static control e.g. frames, icons, rectangles
         WVBXControl     - VBX control
     WDDEClient      - DDE client
     WDDEServer      - DDE server
     WDialog         - dialog window
         WDBrowse        - browser using a dialog
         WProgressDialog - progress bar dialog
         WToolbarDialog  - toolbar using a dialog
         WVBXDialog      - a dialog with VBX controls
     WWindow         - simple window
         WFrameWindow    - feature-rich (container) window
             WMDIChild       - MDI child
             WMDIFrame       - MDI main (top-level) window
             WSDIWindow      - SDI main (top-level) window
         WMDIClient      - MDI client
         WStatusBar      - status (message) bar
         WToolbar        - toolbar
         WToolbarTip     - toolbar tip (balloon help)