Download High quality mp3 audio, and use video title as file name

youtube-dl -o '%(title)s.%(ext)s' --extract-audio --audio-format mp3 --audio-quality 0 url

Download High quality mp3 audios that have min view 2000, and use video title as file name, 

youtube-dl -o '%(title)s.%(ext)s' --min-view 20000 --extract-audio --audio-format mp3 --audio-quality 0 url

Do not download any videos with less than count views, and use video title as file name

youtube-dl  -o '%(title)s'  --min-views 1000  url

Download best quality video play list and use video title as file name

youtube-dl -o "%(title)s.%(ext)s" -cwi --format best --yes-playlist "url"

-cwi is a shorter alternative to –continue –no-overwrites –ignore-errors

Download the best video 

youtube-dl -f best url

List Available Formats

youtube-dl -F "url"

For more information:

https://github.com/rg3/youtube-dl/blob/master/README.md#readme