What are DLL files? Why Windows uses these files?

DLL stands for Dynamic Library Link, did you ever bothered what are these files are why Windows have enormous amount of these DLL files? Let us understand and get to know the basic concept of using DLL files.

Hello everyone, welcome back to Intelligent computing.

Introduction to Software System

Do you know there are broadly two types of programes, one that is single executable files like those that we use to create in C or C++ languages & another is one or many executable files with many other files like those that we use in Windows or in many programes.

However, let me remind you, we usually uses the Software not a programe. Defining software as “Collection of interconnected programes used for many purpose”. Therefore, we cannot have our purpose solved by one single programe. We need lots of and many programes to do even single work.

Example playing MP3 files on your Windows 7 System used to call hundreds of programes, plugins, drivers, services and much more. It involves retrieving MP3 files to RAM decoding it according to bit rate, uses the MP3 decoding plugins, calling device driver for audio and accessing the Windows Audio service, calling Visualization plugin, loading Media player skin and many more. In addition, you can think of thousands of programes are involved for this purpose.

DLL Helps in Code reusability

Now think can we integrate 1000s of programe to one file and make a single programe to play MP3 music. Yes, we can. However, think of same process with little changes is going to run when we will play a WAVE file. We may again need to have to access files used in MP3 files but now we have to make another big programe of 1000 programe for WAV in which most of the files will be same as in MP3 player.


I think you are getting what I am saying. Let us pause this discussion here only, look at another aspect.


As you keep adding the features in a program and keeping one single file, you are supposed to increase the exe file size more and more. Adding and removing features are not possible as once file is compiled it becomes binary file and no modification can be done after that.

DLL helps in Lighting Loads on Computer

Another problem will be memory usage. Think of a software which have 100s of feature and file size of 500MB and I need to use only 3 features of them but what I need to do is load whole 500 MB software to RAM and execute it and get to use only 3 features, how crappy is that For Performance for RAM and for power consumption.


DLL files are Dynamic Library Link files, which have collection of similar programes, which are not having any such application or usability as alone. These files are kind of features that main executable file uses during the execution.

DLL helps in keeping Main Executable file small

We need to execute only one single file to run a software program, this one file have indexes that loads different DLLs and EXE files when needed, keeping the program dynamic in nature and only usable files are loaded into RAM rest are just reside either in Hard drive or in Virtual Memory.

Can we open DLL files or Modify It?

The Answer is yes!

I had done this, you need to know that alone DLL files are of no use, it has many things that needs to be called by main program, for example a Sound effect called Scratch.dll may be present in an Audio player, we can use this effect while playing audio, but alone Scratch.dll have no use.

You can still find many things that you will love to explore, you can Download resource hackerApplication and install this. Right click on any DLL file and open with RH. You can see lots and many things inside it, you can explore the options and modify it making sure this will affect your program and it little mistake may cause program being damaged.
So keep one backup of that file you are modifying.

Bottom line

DLL file keeps executable files size small, makes the program dynamic, portable, editable, modifiable memory efficient, power and processing efficient. We can use the linking of different files in one single executable file of tiny size to minimize the load. We can view the content of DLL files using resource hacker and modify its content up-to certain limit. But these modification may cause serious error in Software or dependent programe’s functionality.

Hope you find this post usable and informative, share this in your friends circle by tweeting this, pinning this, +1 this and Liking this post.
Dheeraj thedijje

Dheeraj thedijje

Powered by Blogger.