pacman is a package manager written specifically for Arch Linux. Developed by Arch Linux
License: Open Source
aptitude is a terminal-based apt frontend with a number of useful features, including: a mutt-like syntax for matching packages in a flexible manner, dselect-like persistence of user actions, the ability to retrieve and display the Debian changelog of most packages, and extreme flexibility and customization.
License: Open Source
Pacman is a lightweight and efficient package manager designed specifically for Arch Linux, focusing on speed and simplicity. In contrast, Aptitude offers a more comprehensive dependency resolution system and a user-friendly GUI, making it better suited for users who prefer a graphical interface and need advanced package management features.