| Data Member | Description |
| m_atom | Uniquely identifies the registered window class. |
| m_bSystemCursor | Specifies whether the cursor resource refers to a system cursor or to a cursor contained in a module resource. |
| m_lpszCursorID | Specifies the name of the cursor resource. |
| m_lpszOrigName | Contains the name of an existing window class. |
| m_szAutoName | Holds an ATL-generated name of the window class. |
| m_wc | Maintains window class information in a WNDCLASS structure. |
| PWndProc | Points to the window procedure of an existing window class. |