The components of the link archive are loaded only when the program requires them. The DLL modules make basic functions available, like for example device drivers, routines for the memories, file and directory services, functions for cursors, menus and windows, interface functions like the CAPI.dll, which makes the access possible to an ISDN map.
DLLs are used in the Windows and OS/2 operating systems and can be used simultaneously by several applications. In addition, DLLs also enable programming language programming. DLLs contain important functions that control the internal software and hardware interfaces in certain operating systems.
The file extension for DLL files is *.dll.