YouTube is a great place that allows you to watch, upload and share videos on the internet. But it doesn't allow you to download that amazing video that you watched. YouTube Catcher is an online tool that allows you to download videos from YouTube .You can also convert the video in to other format or can be extract only audio from the video. Copy and paste the URL of the YouTube Video and click the 'downlod' button to start. Rename the file with .flv extension.