Download Youtube videos for free, No software required

I am going to tell you one of the fantastic way to download youtubevideos in .flv format without the use of any software.
STEPS
1. Copy the URL of the video and paste it in the address bar.
2. Remove the words youtube.in or youtube.com and paste voobys instead of it.
3. Don't change anything else in the address except the words mentioned above.
4. Press Enter.
The video would be downloaded in flv format.Use an flv player like the VLC Media player to watch the videos.