First of all, It’s possible to install R from the Ubuntu Software Center
But it’s so outdated, so some packages won’t work for maintenance issues.
To be able to install the current version you must modify the file sources.list
To do that, go to the terminal and type:
sudo nano /etc/apt/sources.list
And you should add the following line:
deb http://dirichlet.mat.puc.cl//bin/linux/ubuntu trusty/
That adress is because I’m on Chile, thus you have to replace it for the right mirror belonging to your country. To know that, just go to:
After you have modified the sources.list type the following:
sudo apt-get install r-base
sudo apt-get install r-base-dev
And now you have R ready to use it. Though, I recommend to use it along with RStudio.