After the official release of a distribution, the developers continue to iron out bugs with various patches, and they continue to minimize security vulnerabilities during the entire support period of the operating system. Ubuntu 17.04, for example, will be supported for the next 9 months. If you install the distribution a few weeks after its official release, updates are already available.

To look for updates, call up the Software Updater program (Figure 1), which displays a list of installable patches. Clicking Install Now downloads the patches onto your computer (Figure 2). Restart the system to apply the patches. If no updates are available, you will see The software on this computer is up to date (Figure 3).

Bug fixes help keep your system safe and secure. With a few exceptions, such as Firefox and Thunderbird, newer versions of installed programs are updated with the next Ubuntu version. Within the support cycle of Ubuntu 17.04, only Backports and PPAs [1] can be applied to a new version. Backports are special repositories that provide newer versions of some software [2].

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