In case you were wondering, use youtube-dl as a ...
downloader of videos from YouTube and other sites
youtube-dl is a small command-line program to download videos from
YouTube.com and other sites that don't provide direct links to the
youtube-dl allows the user, among other things, to choose a specific video
quality to download (if available) or let the program automatically
determine the best (or worst) quality video to grab. It supports
downloading entire playlists and all videos from a given user.