The Advanced Package Tool (APT) was developed to provide a better command line tool, that provides the download and dependency resolution of dselect without requiring a separate utility for installation. Think of it as an all-in-one command line tool that can select and install or remove packages, and automatically resolve dependencies.
APT is actually a set of utilities that include apt-get, the basic package installation tool, plus several other command line tools with an apt prefix that provide additional functions, such as reporting on available software, and other basic local repository maintenance functions.
The man apt command is a good starting point, as it references other man pages for the additional commands. The Debian reference manual also has a lot of information on these and other package management commands
This tool is fast and, except in unusual circumstances, handles dependencies without requiring user intervention. Itis the basic tool used for automatic, unattended software installation and updating.
