It happens that as our system is updated, new Linux kernels are installed. The previous stay in the system in case we need to use them. This is clearly seen at boot selection screen in the operating system's grub.

In addition to the overhead menu grub for Linux kernels no longer going to use, they occupy a significant volume on your hard drive.

Is quite easy to remove by using a terminal. We opened one by pressing CTRL + ATL + T or from Applications -> Accessories -> Terminal.

If our system is not installed install it with aptitude

sudo apt-get install aptitude

Once installed aptitude we will serve it to know the core installed using the following command:

aptitude search ~ilinux-image-2

It displays a list of the installed kernels. Of these one is that we are using and we should not delete it. Surely be the most recent, as indicated by its version number. The latest is the one with higher version number. To ensure we can use the following command that indicates the kernel.

uname -r

Once we know what NOT to delete can start deleting the oldest. The command to do is:

sudo aptitude purge nombre_del_kernel

Where nombre_del_kernel by the corresponding change to the kernel you want to delete. After a few seconds the kernel will be deleted.