Window-creation functions create, destroy, modify, and obtain information about windows. Following are the window-creation functions:
| Function | Description |
| AdjustWindowRect | Computes the size of a window to fit a given client area. |
| AdjustWindowRectEx | Computes the size of a window with extended style to fit a given client area. |
| CreateWindow | Creates overlapped, pop-up, and child windows. |
| CreateWindowEx | Creates overlapped, pop-up, and child windows with extended styles. |
| DefDlgProc | Provides default processing for messages that an application-defined dialog box procedure does not process. |
| DefFrameProc | Provides default processing for messages that an application-defined MDI frame window does not process. |
| DefMDIChildProc | Provides default processing for messages that an application-defined MDI child window does not process. |
| DefWindowProc | Provides default processing for messages that an application-defined window procedure does not process. |
| DestroyWindow | Destroys a window. |
| GetClassInfo | Retrieves information about a specified class. |
| GetClassLong | Retrieves a long value from the extra class memory associated with a window. |
| GetClassName | Retrieves a window-class name. |
| GetClassWord | Retrieves a word value from the extra class memory associated with a window. |
| GetLastActivePopup | Finds out which pop-up window owned by another window was most recently active. |
| GetWindowLong | Retrieves a long value from the extra window memory associated with a window. |
| GetWindowWord | Retrieves a word value from the extra window memory associated with a window. |
| RegisterClass | Registers a window class. |
| SetClassLong | Set a long value in the extra class memory associated with a window. |
| SetClassWord | Set a word value in the extra class memory associated with a window. |
| SetWindowLong | Set a long value in the extra window memory associated with a window. |
| SetWindowWord | Set a word value in the extra window memory associated with a window. |
| UnregisterClass | Removes a window class from the window-class table. |
For detailed information about the window-creation functions, see the Microsoft Windows Programmer's Reference, Volume 2.