Windows: Change file extensions - how it works

On Windows 7, the procedure is similar:

1. Open the folder with the files to be changed in Windows Explorer.
2. Click on "Organize" in the menu bar and then on "Folder and search options".
3. Switch to the "View" tab. Uncheck "Hide extensions for known file types" and close the window with "OK".
4. Mark a file in Windows Explorer and press the [F2] key. You can now easily change the file extension and rename the item.