The most common Youtube app downloader there is youtube-dl, I am pretty sure that it is available in Ubuntu’s, Debian’s, Arch’s, Gentoo’s and OpenSUSE repos; but it is certain that it is available in a bunch of distros.
In Ubuntu and Debian you may install it with this command:
sudo apt-get install youtube-dl
I think this is the first Link from Google when searching for a Linux Youtube Music player: Link ; however, there is a lot of answers and some of them are complex. For the sake of simplicity I will share with you the most straightforward resolution to me:
mplayer <(youtube-dl -q -f bestaudio[ext=m4a] "$URL" -o - )
Mplayer is a command-line media player very usual in the Linux systems, so you may need to install it first.
I made it easier for you:
read -p "paste the url please:" URL ; mplayer <(youtube-dl -q -f bestaudio[ext=m4a] $URL -o - )
And I created this shortcut so you will never miss this command: In a terminal type the following for displaying the adequate command :
(That is one of the reasons that my website is named curl, to not forget)
The full command will ask you for input the youtube URL.
After the mplayer command is the youtube-dl command, which is surrounded by parenthesis starting with a lesser than symbol. The whole output of this command will be treated as a file, so that it ends in a hyphen meaning that the resulting extraction will be redirected to standard output.