Ubuntu users often runs these commands. When you setting up a server for production deployment, these commands are the first ones to run. Same time it is important to understand what those commands do.
apt-get update VS apt-get upgrade
|apt-get update||apt-get upgrade|
|Updates the list of available packages and their versions, but it does not install or upgrade any packages||Installs newer versions of the packages you have. After updating the lists, the package manager knows about available updates for the software you have installed.|
|will update your local copies of your repositories’ package data, such as available versions and dependencies.||The former runs general system upgrades. It will apply higher level patches such as kernel upgrades.|
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