đź§°

Ubuntu Apt Package Manager Overview

Jul 20, 2025

Overview

This lecture covers the use of the apt package manager in Ubuntu, including installing, removing, and updating software packages, as well as managing repositories.

Apt Package Manager Basics

  • apt (Advanced Package Tool) is used in Ubuntu to manage software packages easily.
  • It extends the functionality of dpkg by handling dependencies and simplifying installation and removal processes.
  • apt can automatically install dependencies required for packages.

Installing and Removing Packages

  • Use sudo apt install <package> to install software; apt fetches and installs required dependencies.
  • apt gives a summary of package changes after installation (e.g., number of packages installed or upgraded).
  • Remove software with sudo apt remove <package>; apt also removes unneeded dependencies.

Package Repositories

  • Repositories are central servers storing software packages for download and installation.
  • Package repositories eliminate the need to manually search for software online.
  • In Ubuntu, repository sources are listed in /etc/apt/sources.list.
  • Ubuntu includes default repositories for base OS packages and essential tools.

Personal Package Archives (PPAs)

  • PPAs are special repositories hosted on Launchpad servers, maintained by developers.
  • Add PPAs like regular repositories, but use caution—PPA content may be less vetted and potentially unsafe.

Updating Software and Repositories

  • Run apt update to refresh the package list from repositories—this does not install or upgrade software.
  • Run apt upgrade to install new versions of outdated packages.
  • It's recommended to run apt update and apt upgrade before installing new software for the latest versions.

Apt Command Help

  • Use apt help to see available apt commands and options, such as searching or listing packages.

Key Terms & Definitions

  • apt — Advanced Package Tool, Ubuntu’s package manager for installing, removing, and managing software.
  • Repository — Central server storing software packages accessible by apt.
  • PPA (Personal Package Archive) — User-maintained repository hosted on Launchpad, often for specific or non-standard software.
  • /etc/apt/sources.list — File listing repository sources used by apt.

Action Items / Next Steps

  • Refer to the provided GIMP download link for practice.
  • Before installing new software, run sudo apt update and sudo apt upgrade.
  • Use apt help to explore more packaging commands.