youtube-dl flags code example
Example 1: downloading youtube playlists using youtube-dl in highest quality
youtube-dl -f 22 'http://www.youtube.com/watch?v=P9pzm5b6FFY'
Example 2: youtube-dl don't replace videos
youtube-dl --download-archive downloaded.txt --no-post-overwrites -ciwx --audio-format mp3 -o "%(title)s.%(ext)s" [path here]