How do I download a YouTube video?

youtube-dl

Installation from official site:

sudo curl -L https://yt-dl.org/downloads/latest/youtube-dl -o /usr/local/bin/youtube-dl
sudo chmod a+rx /usr/local/bin/youtube-dl

It's also on Ubuntu repos but you will often need to keep it up-to-date with sudo youtube-dl -U

Installation and ugrade from pip (/):

sudo -H pip install --upgrade youtube-dl

Usage:

youtube-dl YouTube-(or-other-website)-video-link

So it will download the video.

You can also take a look at this for very in-depth documentation on how to use it.

youtube-dl is a great tool for downloading YouTube videos. Install with:

sudo curl -L https://yt-dl.org/downloads/latest/youtube-dl -o /usr/local/bin/youtube-dl
sudo chmod a+rx /usr/local/bin/youtube-dl

Or with pip (python3-pip):

sudo -H pip install --upgrade youtube-dl

Or from Ubuntu's repo (older version)

sudo apt-get install youtube-dl

then use it this way:

youtube-dl [VIDEO_LINK]

For learning more about advance options, run

man youtube-dl

Or check out the documentation.

Original answer

For Firefox users:

You can install the Video DownloadHelper addon in Firefox and download any embedded object, including YouTube videos.

Minitube

Minitube is a YouTube desktop application. With it you can watch YouTube videos in a new way: you type a keyword, Minitube gives you an endless video stream. Minitube is not about cloning the original YouTube web interface, it aims to create a new TV-like experience.

It does not require Flash Player. From this application you can watch and download videos.

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