Updating linux mint
First, open the Terminal application and type following two commands (Application Please note that above two commands will fetch files from the Internets or local mirrors.
The location of update pages is specified in /etc/apt/(repositories).
In the process you might also learn how to install an application or two.
There is one thing to understand about updating Linux: Not every distribution handles this process in the same fashion.
In fact, some distributions are distinctly different down to the type of file types they use for package management.
The updates will proceed and you can continue on with¬† your work.
So to make the task of covering this topic less epic, I will cover the Ubuntu and Fedora systems.