from the Internet
with the official server, called a repository.
all off.signed sustainable repository of digital keys, and never heard anything about the switch package.
. if you have access to the installation packages you can make the system anything because the ordinary user is usually not trusted. and the basic rule "don't run as root".
plus there is the ability to connect third-party repositories.
for example chrome is basically a repository of a system usually appears with great delay.
so Google, for lovers of fresh, has its own repository, which puts the latest builds for chrome.
what to connect to it you must install the system key, which is signed rap Google, and set the path to the repository. After that will be the most recent chrome from all connected repositories.