Some applications in Ubuntu don't update automatically, for example VirtualBox, GCC and Git.
I'm afraid of using unofficial PPAs, but I can't find PPAs from official sources.
For Finding PPA:
For getting Information about PPA and use, visit:
From community PPA:
PPAs have not undergone the same process of validation as regular ubuntu packages. End users install PPAs at their own risk. Although each key is cryptographically signed, in order to confirm an uploader, keys are not matched to specific individuals, except via their "launchpad" accounts.
Subsequently, installing a PPA should be considered to be a low-security alternative as compared to the main repository, but marginally higher security than simply installing software at random from the internet. As part of adding a PPA, you trust the developer to not only install packages, but also to allow them to provide ongoing updates.
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