About this tutorial

This tutorial's examples are done in Devuan Stable 5.0 ( Daedalus ) (based on debian stable 12.0 (bookworm) . The Devuan is running on a qemu virtual-emulated machine.

Offered functionality

What is APT ?

apt is an utility that downloads and installs packages from repositories (repos) that contain deb packages.

What is a repo ?

$ less /etc/apt/sources.list
deb http://deb.devuan.org/merged daedalus main contrib non-free non-free-firmware

---++ apt binaries 
$ ls -alh /usr/bin/apt-get 
-rwxr-xr-x 1 root root 51K May 28  2023 /usr/bin/apt-get
$ ls -alh /usr/bin/apt
-rwxr-xr-x 1 root root 19K May 28  2023 /usr/bin/apt

Let's see the contents of package apt :

$ dpkg -L  apt
/usr
/usr/bin
/usr/bin/apt
/usr/bin/apt-cache
/usr/bin/apt-cdrom
/usr/bin/apt-config
/usr/bin/apt-get
/usr/bin/apt-key
/usr/bin/apt-mark

Asymmetries in package removal

When a package is installed apt will also install it's Depends and Recommends packages (but by default not Suggests ones) .