dpkg is the primary package manager for Debian and Debian-based systems, such as Ubuntu.
Check if a package is installed or not
Display details about a package
Hold a package
Install a package
Install all packages recursively from directory
List packages
Purge a package
Reconfigure a package
Remove a package
Unhold a package
Update repositories
Upgrade a package
What files are provided by the package
What files are provided by the installed package
What package owns a file