apt-get install youtube-dl

The following extra packages will be installed:
  liba52-0.7.4 libaacs0 libasound2 libasound2-data libass4 libasyncns0
  libav-tools libavcodec54 libavdevice53 libavfilter3 libavformat54
  libavresample1 libavutil52 libbluray1 libbs2b0 libcaca0 libcdio-cdda1
  libcdio-paranoia1 libcdio13 libdc1394-22 libdca0 libdirectfb-1.2-9
  libdrm-nouveau2 libdv4 libdvdnav4 libdvdread4 libenca0 libfaad2 libflac8
  libgif4 libgl1-mesa-dri libgl1-mesa-glx libglapi-mesa libgsm1
  libjack-jackd2-0 liblircclient0 libllvm3.4 libmad0 libmp3lame0 libmpg123-0
  libogg0 libopenjpeg2 libopus0 liborc-0.4-0 libpostproc52 libpulse0
  libquvi-scripts libquvi7 libraw1394-11 libsamplerate0 libschroedinger-1.0-0
  libsdl1.2debian libsndfile1 libspeex1 libswscale2 libtheora0 libts-0.0-0
  libtxc-dxtn-s2tc0 libva1 libvdpau1 libvorbis0a libvorbisenc2 libvpx1
  libx11-xcb1 libx264-142 libxcb-dri2-0 libxcb-dri3-0 libxcb-glx0
  libxcb-present0 libxcb-sync1 libxdamage1 libxfixes3 libxinerama1
  libxshmfence1 libxss1 libxv1 libxvidcore4 libxxf86vm1 mplayer2 rtmpdump
  tsconf x11-common
Suggested packages:
  libasound2-plugins alsa-utils frei0r-plugins libbluray-bdj libdv-bin
  oss-compat libdvdcss2 build-essential debhelper fakeroot libglide3 jackd2
  lirc opus-tools pulseaudio libraw1394-doc speex nvidia-vdpau-driver
  vdpau-driver ffmpeg mplayer
The following NEW packages will be installed:
  liba52-0.7.4 libaacs0 libasound2 libasound2-data libass4 libasyncns0
  libav-tools libavcodec54 libavdevice53 libavfilter3 libavformat54
  libavresample1 libavutil52 libbluray1 libbs2b0 libcaca0 libcdio-cdda1
  libcdio-paranoia1 libcdio13 libdc1394-22 libdca0 libdirectfb-1.2-9
  libdrm-nouveau2 libdv4 libdvdnav4 libdvdread4 libenca0 libfaad2 libflac8
  libgif4 libgl1-mesa-dri libgl1-mesa-glx libglapi-mesa libgsm1
  libjack-jackd2-0 liblircclient0 libllvm3.4 libmad0 libmp3lame0 libmpg123-0
  libogg0 libopenjpeg2 libopus0 liborc-0.4-0 libpostproc52 libpulse0
  libquvi-scripts libquvi7 libraw1394-11 libsamplerate0 libschroedinger-1.0-0
  libsdl1.2debian libsndfile1 libspeex1 libswscale2 libtheora0 libts-0.0-0
  libtxc-dxtn-s2tc0 libva1 libvdpau1 libvorbis0a libvorbisenc2 libvpx1
  libx11-xcb1 libx264-142 libxcb-dri2-0 libxcb-dri3-0 libxcb-glx0
  libxcb-present0 libxcb-sync1 libxdamage1 libxfixes3 libxinerama1
  libxshmfence1 libxss1 libxv1 libxvidcore4 libxxf86vm1 mplayer2 rtmpdump
  tsconf x11-common youtube-dl