Intel® Fortran Compiler 17.0 Developer Guide and Reference
You can organize the code in your application by storing the executable code for certain routines in a shareable library (.dll for Windows*, .so for Linux*, or .dylib for OS X*). You can then build your applications so that they call these routines from the shareable library.
When routines in a shareable library are called, the routines are loaded into memory at run-time as they are needed. This is most useful when several applications use a common group of routines. By storing these common routines in a shareable library, you reduce the size of each application that calls the library. In addition, you can update the routines in the library without having to rebuild any of the applications that call the library.