Even though DLLs and applications are both executable program modules, they differ in several ways. To the end user, the most obvious difference is that DLLs are not programs that can be directly executed. From the system's point of view, there are two fundamental differences between applications and DLLs:

An application can have multiple instances of itself running in the system simultaneously, whereas a DLL can have only one instance.
An application can own things such as a stack, global memory, file handles, and a message queue, but a DLL cannot.

What do you want to do?

Export from a DLL
Link an executable to a DLL
Initialize a DLL

What do you want to know more about?

The advantages of using DLLs
Non-MFC DLLs: Overview
Regular DLLs statically linked to MFC
Regular DLLs dynamically linked to MFC
Extension DLLs: Overview

What do you want to do?

What do you want to know more about?

See Also

Concepts