Previously, we explained the difference of streaming and downloaded videos. YouTube and Google Videos are streamed, so you are not given the option of saving the videos locally. But sometimes you might just want to store a local copy.

And this can be for several reasons. First, there are chances that videos can be taken down from YouTube and Google Video–this is primarily because of copyright. Secondly, you might want to save a local copy for archive. This can come in handy when you want to watch videos even when not connected to the Internet. Of course, consider that YouTube and Google Videos are low quality (maybe you’d want a DVD or a higher-res downloaded video for that.

KeepVid keeps it simple. You just input the URL of the video you want to save and it then lets you download the file as an .FLV flash video. You don’t need to know the direct URL of the flash video itself, but you can simply input the URL of the YouTube or Google Video page and KeepVid does the rest.

So for instance, we want to download this Ask a Ninja video from YouTube, with the URL http://youtube.com/watch?v=qdS5lkeN8_8. We just paste in that URL on the URL box on KeepVid.

Then KeepVid will give us the direct download URL for the flash video: http://sjc-v40.sjc.youtube.com/get_video?video_id=qdS5lkeN8_8.

You then have to click the link to save locally. Your browser may ask you to confirm the download.

Once you have downloaded the file, you can then watch it on any compatible player. YouTube downloads should, for instance, be in the .FLV extension, and you can play these through free .FLV player such as the one available for free download here.