If you’ve ever tried to delete a file that Windows wants to cling to, especially if the file is inside the system32 folder you will see a message like that “The file x is a system file”.
Many of the files inside system32 take the form of dynamic link libraries or DLL’s, these files contain code and data that can be accessed and shared by many programs including windows. The DLL’s inside the folder enable functionality from control panel options to error checking, system updates, streaming media, encryption services, audio and video playback, Directx rendering and even the windows interface itself.
It also includes most of your drivers as well as elements of the Windows kernel the fundamental code that interfaces Windows with your hardware, allowing it to work well. Many of these files simply can’t be deleted after you boot into Windows, since they’ve already been loaded into memory, but even deleted other system32 files will probably end up breaking a number of obvious things on your system and result in your computer refusing to boot the next time you try to turn it on.
There are many people on the internet think that if you delete the system32 folder, it will speed up your computer. The moral story is: don’t delete the system32 folder and don’t take computer maintenance advice from unknown people.