LibreOffice is developed by forking the OpenOffice(Probably due to the fact that Oracle had bought the Sun MicroSystems,therefore the future of OpenOffice wasn’t good in the hand of Oracle). It is free,open source and cross-platform(Linux,Windows and Mac). LibreOffice is the best substitute for Microsoft Office. LibreOffice is very useful for creating and editing Text Documents,Drawing,Spreadsheet,Presentation etc.
Ubuntu ships OpenOffice by default so, if you want to install Libre Office then first remove the OpenOffice package(use Synaptic Package Manager). Then install the LibreOffice by typing the commands written below -
First Add the PPA Repository -
sudo add-apt-repository ppa:libreoffice/ppa
Then Update the Repository -
sudo apt-get update
Now install gnome version of LibreOffice -
sudo apt-get install libreoffice && sudo apt-get install libreoffice-gnome