1. Navigate to the directory where you want to create such type of folder.
2. Hold Shift key and Right click mouse button. Select "Open Command Window Here" option.
You can also traverse using cd (Change Directory) command.
cd stands for: Channge Directory.
4. The folder having name as "con" is now created in your directory. Place your secrete files into this folder. Now just try to rename or delete it, Definitely it will give an error!
5. To delete this folder, Come back on command prompt window and type "rd con\" and hit Enter!
rd stands for: Remove Directory
6. Similarly try to change con with other reserved keywords such as aux, lpt1, lpt2, lpt3, lpt4, lpt5, lpt6, lpt7, lpt8 and lpt9. You will get same result!