The file formats for DLLs are the same as for Windows EXE files - that is, Portable Executable (PE) for 32-bit and 64-bit Windows, and New Executable (NE) for 16-bit Windows. These libraries usually have the file extension DLL, OCX (for libraries including ActiveX controls), or DRV (for legacy system drivers). Dynamic-link library or DLL, is Microsoft’s implementation of the shared library concept in the Microsoft Windows and OS/2 operating systems.
