The difference between .exe and .dll files is crucial in the world of Windows operating systems, as they play distinct roles in running and managing software.

EXE and DLL are both PE (Portable Executable) file format. The only Difference- EXE is exporting WinMain() and DLL is exporting DllMain() functions. By memory allocation – they are loaded into different memory ranges. EXE can have own address space but DLL can’t. DLLs are merged to address space of EXE’s.

Difference Between .DLL and .EXE Files

Key-Function	.EXE Files	.DLL Files
1. Purpose and Functionality	These are standalone files that, when run, launch an application or software program on your computer. They contain all the necessary code, resources, and metadata to execute the program’s functions independently.	Unlike .exe files, .dll files cannot be executed directly. They exist to store functions, procedures, and resources that other programs can use. Multiple applications can access and use the functions stored in a single .dll file simultaneously, promoting code reusability and efficient memory usage.
2. Dependency and Interaction	An executable file is self-sufficient and does not depend on other files to run. However, it may call upon .dll files to access additional functions or resources needed for its operations.	These files are dependent on executable files or other .dll files to be called into action. They do not run on their own but are invoked when a running application requires the functions or resources they contain.
3. Memory Management	When you run an .exe file, it gets its own memory space, ensuring that its operations do not interfere with other running applications.	.dll files are designed to be shared across multiple applications, allowing them to run in the same memory space. This promotes efficient memory usage but also means that errors in a .dll file can affect all applications using it.
4. Compilation and Linking	These files are compiled and linked to create a standalone application. All the necessary code and resources are bundled together during the compilation process.	.dll files are compiled separately and can be linked dynamically at runtime. This means that updates to a .dll file can be made without needing to recompile the entire application.
5. Distribution and Updates	When distributing an application, the .exe file is the main component that users need to run the software. Any updates to the application typically require redistributing the entire .exe file.	.dll files can be distributed separately from the application, allowing for easier updates. If a function in a .dll file is updated or fixed, only the .dll file needs to be redistributed and replaced, not the entire application.

FAQ.1 : Do DLLs share the same format as EXE files?

Ans. : Yes, DLLs share the same format as Exe files. However, the format varies, the 16 bit Windows uses New Executable (NE), while the 34-bit and 64-bit one use Portable Executable (PE).

FAQ.2 : Can an EXE be a DLL?

Ans. : No, EXE can’t be a DLL even if they share the same format because they serve different purposes. An EXE is a program that runs on its own, while a DLL is a file that helps other programs run.