Interesting notepad trick

Steps to hide text in a Notepad:
1. Open your command prompt Start-->Run and Type cmd
2. Type cd.. to move to C:\> drive or Type cd desktop to move to your desktop.
3. Type the below code in your command prompt
notepad filename.txt:hidden
4. Write some data and save(Ctrl+S) the file.
5. Browse to the file location and Open filename.txt you cannot see any data in the file.
6. To retrieve the hidden data open command prompt and type the same command.
notepad filename.txt:hidden