APT (Advanced Packaging Tool) is a set of tools that was developed for Debian Linux platform as an easy command line interface for the dpkg utility
apt update
apt upgrade
apt install python3
apt install ./pi4j-1.3.deb # install local package
apt show python3
apt remove python3
apt list # lists all available packages
apt list --installed # lists installed packages
apt list python3 # also shows if package is installed
apt search python3
# list all files contained in the package
dpkg -L python3
# find which package contains a file
dpkg -S /usr/bin/python3
