It is quite easy to download public videos from Facebook. If you have the video link that you wish to download, all you need to do is copy it and then paste it into the input box. After you paste the link, click the "download" button which will redirect you to another page. You will be able to select the link you want to download. GetfVid is free to use and no registration is required.
If you want to download private videos from Facebook, you can do that with a private video downloader such as fbvidsdownload.com/private-downloader. Usually, only those who are able to see the video's code can download it. Using this tool allows you to capture the video and it still allow it to remain private. Of course, you should still always respect the copyrights of the videos you are downloading.
When you're downloading files, they are usually saved into whatever folder you have set as your default. Your browser normally sets this folder for you. In browser settings you can change and choose manually the destination folder for your downloded facebook videos.
Once streaming is done, you can easily save live FB videos to your device using Video Downloader for Facebook chrome extension.
Video Downloader for Facebook doesn't store videos. Neither do we keep copies of downloaded videos. All videos are hosted on Facebook's servers. Also, we don't keep track of the download histories of our users, thus making using Video Downloader for Facebook totally anonymous.