Step 1:- Open the terminal and type sudo apt-get install youtube-dl
Step 2:- After when it installed then update it to the stable version by typing this command sudo youtube-dl --update
Step 3:- Now copy the URL of the video which you wana download.
Step 4:- For downloading the video use this below command
youtube-dl "http://www.youtube.com/watch?v=huV8zV-e-Fo"
Step 5:- now see the video will be downloaded into your HOME directory rename it and enjoy.
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