Question of terminology and classification.
Is DLL an "executable file"?
Super User is a question and answer site for computer enthusiasts and power users. It only takes a minute to sign up.Sign up to join this community
A DLL file is not by it self executable, though it may contain executable code. A DLL (Dynamic-Link Library) contains code, data, resources etc. usable by other programs. You need an EXE file for the operating system to execute code within DLL files, like "RUNDLL.EXE" or "RUNDLL32.exe" in windows.
According to the Wikipedia article a DLL is an executable file.
In computing, an executable file causes a computer "to perform indicated tasks according to encoded instructions," as opposed to a data file that must be parsed by a program to be meaningful.
Taking this definition a DLL is an executable because it contains encoded instructions to perform a task.
The exact interpretation depends upon the use; while the term often refers only to machine code files, in the context of protection against computer viruses all files which cause potentially hazardous instruction execution, including scripts, are conveniently lumped together.
This is also true for DLLs.
But some might argue that a DLL cannot run by itself, it always needs some program which loads the DLL and calls a function exported by the DLL, so in a strict sense you might also say that only exe-files (if on Windows) are executable files. As Wikipedia says...
The exact interpretation depends upon the use
I would try to use terms or phrases that make it more clear and avoid speaking of executable files if it is not clear in the given context if DLLs are included or not. Even at my work (software developer) I'ld not be sure that everyone always would agree that "executable files" also means DLLs.
DLL files contain executable code, but it's not all-sufficient.
Usually, DLL file contains library functions, helpers.