Update Package Index
The ‘update‘ command is used to resynchronize the package index files from the their sources specified in /etc/apt/sources.list file. The update command fetched the packages from their locations and update the packages to newer version.
$ sudo apt-get update
Search Package Index
Apt-cache is use to search for an available package from the repositories.
$ sudo apt-cache search packagename
Examine Package Details
Apt-cache is used to find details of a package
$ sudo apt-cache show packagename $ sudo apt-cache showpkg packagename
Install a Package
Use apt-get to install a package:
$sudo apt-get install packagename
Upgrade Installed Packages
The ‘upgrade‘ command is used to upgrade all the currently installed software packages on the system. Under any circumstances currently installed packages are not removed or packages which are not already installed neither retrieved and installed to satisfy upgrade dependencies.
$ sudo apt-get upgrade
List Installed Packages
Upgrade Specific Packages
Use install to upgrade specific pacakges.
$ sudo apt-get install packagename
Remove Specific Package
$ sudo apt-get remove packagename $ sudo apt-get --purge remove packagename