Object Windows Library
Object Windows Library（簡稱OWL），由Borland公司在Turbo Pascal for Windows時所推出，可自動完成許多由設計者自行撰寫的程式碼，他的竸爭對手是Microsoft Foundation Class Library（MFC）。其後繼者為VCL。
版本
| Product version | OWL version |
|---|---|
| Borland C/C++ 3.1 | OWL 1.0 |
| Borland C/C++ 2.0 for OS/2 | OWL 2.0 |
| Borland C++ 4.0x | OWL 2.0 |
| Borland C++ 4.5x | OWL 2.5 |
| Borland C++ 5.0x | OWL 5.0 |
| Borland C++ 5.0x Japanese | OWL 5.0 |
| Borland C++ Builder 4.0 | OWL 5.0 |
| Borland C++ Builder 5.0 | OWL 5.0 |
| Borland C++ Builder 2007 | OWLNext 6.20 |
| Turbo Pascal for Windows 1.0 | |
| Turbo Pascal for Windows 1.5 |