Install Minecraft in Ubuntu
I was told Minecraft wasn't available on Linux. Couldn't believe it. Android, Minecraft PE, but not Linux?
So anyway, open a terminal prompt and execute each of those commands in order. You will have to sudo to be able to install.
This is the full Minecraft installation. If you do not have a Majong account, this will allow you to play the evaluation version. If you do have a Majong account you can play full Minecraft.