As much as video portals try their best to prevent downloads (YouTube, for example, even has a paid service that allows it), that's the kind of thing they can make difficult, but they will never be able to stop completely.
The tip we bring you today from a Mac utility specifically designed to make this task easier is VideoDuke, developed by Eltima Software.
What Eltima actually did was extract from Elmedia Player the function of downloading videos. Simply paste or navigate to any URL on YouTube, Vimeo or Dailymotion (as well as other websites with hosted video), which VideoDuke automatically shows you as options for download formats. With one click, you are downloading what you need.
You choose whether you want to download videos in 3GP, MP4, M4V or FLV, and in the resolution you prefer: 360p, HD 720p, Full HD 1080p, etc. If you want, you can even download an MP3 audio version of a particular video.
VideoDuke's interface is very simple and intuitive. It requires macOS Yosemite 10.10 or higher and costs $ 20 in a personal license or $ 40 in a family package for up to three Macs. Interested parties can test a demo and download up to two videos with this version before making the final purchase.