What is free and open source software?

All of the free and open source software listed below is available free of charge. In other words "free, as in free lunch". In addition, much of the following software is "free, as in free speech". These two concepts, although distinct, are often confused. For an in-depth discussion of free and open source software see this Wikipedia article.

Free CD/DVD writing software

• Burn for Mac
  Simple yet advanced burning for Apple OS X.
• Express Burn for Mac
  Create and record audio and data CDs and DVDs.

Free email clients and calendaring

• Mozilla Thunderbird
  Access all your messages, calendars, and contacts in one fast app. Versions of Thunderbird are available for Apple macOS, Microsoft Windows and GNU/Linux.

Free file archiving and compression

• 7-Zip
  A file archiver with a high compression ratio. Available for Microsoft Windows.
• 7zX
  7zX is a file archiver with high compression ratio. Available for Apple macOS.

Free file creation, editing and viewing

• Adobe Reader
  For viewing Adobe Acrobat PDF files. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.
• Apache OpenOffice
  "The Free and Open Productivity Suite." If you are using an unlicenced copy of Microsoft Office on your Windows computer and want to clear your conscience then try switching to OpenOffice - you'll probably love it. If you have installed OpenOffice then you should possibly also install Java listed below.
• Audacity
  For recording and editing sounds. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.
• Blender
  A 3D graphics creation program for Apple macOS, Microsoft Windows, GNU/Linux and FreeBSD.
• CutePDF Writer
  Create professional quality PDF files from almost any printable document. Requires Microsoft Windows.
• GIMP
  For photo retouching, image composition and image authoring.
• FreeOffice
  A free alternative to Microsoft Office for business and personal use.
• LibreOffice
  LibreOffice is a powerful office suite – its clean interface and feature-rich tools help you unleash your creativity and enhance your productivity. LibreOffice includes several applications that make it the most powerful free and open source office suite on the market.
• PDFCreator
  PDFCreator easily creates PDFs from any Windows program. Use it like a printer in any Windows application.
• Scribus
  Scribus is an open-source program that brings award-winning professional page layout to GNU/Linux, Unix, Apple macOS, OS/2 and Windows desktops with a combination of "press-ready" output and new approaches to page layout. Underneath the modern and user friendly interface, Scribus supports professional publishing features, such as CMYK colour, separations, ICC colour management and versatile PDF creation.
• Sublime Text
  Sublime Text is a shareware text and source code editor available for Windows, Apple macOS, and GNU/Linux. It natively supports many programming languages and markup languages.

Free FTP software

• Core FTP
  This free, secure FTP client for Microsoft Windows gives you a fast, easy, reliable way to update and maintain your website via FTP.
• Cyberduck
  With an easy to use interface, connect to FTP (File Transfer Protocol), SFTP (SSH Secure File Transfer), WebDAV (Web-based Distributed Authoring and Versioning), Amazon S3, Google Cloud Storage, Microsoft Azure, Rackspace Cloud Files and even Google Docs. Versions are available for Apple macOS and Microsoft Windows.
• FileZilla
  Both a client and a server are available. FileZilla is open source software distributed free of charge under the terms of the GNU General Public License. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.
• WinSCP
  An open source free SFTP client and FTP client for Microsoft Windows.

Free firewall appliance software

• SmoothWall Express
  An open-source firewall that includes its own security-hardened GNU/Linux operating system and an easy-to-use web interface. The SmoothWall GPL project was founded in the summer of 2000 by Lawrence Manning (Principle Code Author) and Richard Morrell (Project Manager). Their goal was to create a GNU/Linux distribution that could convert a redundant PC into a hardened internet firewall device.

Free software from Apple

• Apple Downloads
  Lots of free downloads directly from Apple to enhance your Mac, PC, iPhone and iPad.

Free media players

• VLC media player
  A cross-platform media player and streaming server.

Free operating systems

• AlmaLinux OS
  An Open Source, community owned and governed, forever-free enterprise Linux distribution, focused on long-term stability, providing a robust production-grade platform. AlmaLinux OS is binary compatible with RHEL®.
• Alpine Linux
  Alpine Linux is an independent, non-commercial, general purpose Linux distribution designed for power users who appreciate security, simplicity and resource efficiency.
• AnduinOS
  AnduinOS is a custom Ubuntu-based Linux distribution that offers a familiar and easy-to-use experience for anyone moving to Linux.
• CentOS Stream
  Continuously delivered distro that tracks just ahead of Red Hat Enterprise Linux (RHEL) development, positioned as a midstream between Fedora Linux and RHEL. For anyone interested in participating and collaborating in the RHEL ecosystem, CentOS Stream is your reliable platform for innovation.
• ClearOS
  ClearOS is an operating system for your Server, Network, and Gateway systems. It is designed for homes, small to medium businesses, and distributed environments. ClearOS is commonly known as the Next Generation Small Business Server, while including indispensable Gateway and Networking functionality. It delivers a powerful IT solution with an elegant user interface that is completely web-based. Simply put, ClearOS is the new way of delivering IT.
• Debian GNU/Linux
  Debian is a free operating system (OS) for your computer. An operating system is the set of basic programs and utilities that make your computer run. Debian uses the GNU/Linux kernel (the core of an operating system), but most of the basic OS tools come from the GNU project; hence the name GNU/Linux. Debian GNU/Linux provides more than a pure OS: it comes with over 25000 packages, precompiled software bundled up in a nice format for easy installation on your machine. It is the solid base on which many other GNU/Linux distributions arebuilt including Ubuntu and GNU/Linux Mint listed elsewhere on this page.
• Debian GNU/Linux Live
  A "live install" image contains a Debian system that can boot without modifying any files on the hard drive and also allows installation of Debian from the contents of the image.
• DragonFly BSD
  DragonFly belongs to the same class of operating systems as other BSD-derived systems and Linux. It is based on the same UNIX ideals and APIs and shares ancestor code with other BSD operating systems. DragonFly provides an opportunity for the BSD base to grow in an entirely different direction from the one taken in the FreeBSD, NetBSD, and OpenBSD series.
• elementary OS
  elementary OS is a free replacement for Windows on the PC and OS X on the Mac. It comes with what you'd expect, like a fast web browser and an app store with thousands of apps. Plus some things you may not expect, like free updates and no known viruses.
• Fedora
  Fedora is a GNU/Linux-based operating system that showcases the latest in free and open source software. Fedora is always free for anyone to use, modify, and distribute. It is built by people across the globe who work together as a community: the Fedora Project. The Fedora Project is open and anyone is welcome to join.
• Fedora Spins
  Alternative desktops for Fedora. Find a Fedora Spin to enhance your experience.
• FlickOS
  Every change has an Undo, and if an update stops your computer from starting, FlickOS goes back to the last working version by itself.
• FreeBSD
  FreeBSD is an advanced operating system for modern server, desktop, and embedded computer platforms. FreeBSD's code base has undergone over thirty years of continuous development, improvement, and optimization.
• FreeDOS
  FreeDOS is a free DOS-compatible operating system that can be used to play games, run legacy software, or support embedded systems. FreeDOS is basically like the old MS-DOS, but better!
• FreshTomato
  FreshTomato is an open source, Linux-based firmware replacement project for home and SOHO WiFi routers.
• GhostBSD
  GhostBSD is a FreeBSD-based operating system engineered to provide a robust, user-friendly desktop experience. Combining the reliability of FreeBSD with the elegance of the MATE desktop environment, we aim to deliver a stable and straightforward computing solution for both everyday users and developers.
• Kali Linux
  Kali Linux is an open source project that is maintained and funded by Offensive Security, a provider of world-class information security training and penetration testing services.
• Linux Lite
  Linux Lite is a lightweight, user-friendly Linux distribution that brings the power of Linux to everyone. Perfect for older hardware and new users alike.
• Linux Mint
  Linux Mint is an Ubuntu-based GNU/Linux distribution whose goal is to provide a more complete out-of-the-box experience by including browser plugins, media codecs, support for DVD playback, Java and other components. It is compatible with Ubuntu software repositories.
• Mageia
  Mageia is a GNU/Linux-based, Free Software operating system. It is a community project, supported by a nonprofit organisation of elected contributors.
• Manjaro
  Taking the raw power and flexibility of Arch Linux and making it more accessible for a greater audience.
• MX Linux
  MX Linux is a cooperative venture between the antiX and former MEPIS communities, using the best tools and talents from each distro. It is a midweight OS designed to combine an elegant and efficient desktop with simple configuration, high stability, solid performance and medium-sized footprint.
• NetBSD
  NetBSD is a free, secure, and highly portable Unix-like Open Source operating system available for many platforms, from 64-bit Opteron machines and desktop systems to handheld and embedded devices.
• NethServer
  NethServer is an operating system for Linux enthusiasts, designed for small offices and medium enterprises. It is based on CentOS/RHEL, a widespread and popular server distribution, trusted by routine security updates, and rock solid stability.
• OpenBSD
  The OpenBSD project produces a free, multi-platform 4.4BSD-based Unix-like operating system.
• openSUSE
  The openSUSE contribution process empowers desktop development for everybody, so you have the choice to pick your favourite one in the installer. We actively feature three desktop environments, and offer even more in the expanded software view within the installer.
• Q4OS
  Q4OS is a fast and friendly, desktop oriented operating system based on Debian Linux. Providing a set of dedicated utilities and specific optimizations, combined with a focus on getting a productive system easily. This makes it ideal for people who want to get a working environment tailored to individual needs and preferences. From this perspective, Q4OS is suitable for both newcomers as well as experienced computer users.
• Trisquel
  Trisquel GNU/Linux is a fully free operating system for home users, small enterprises and educational centers.
• Twister OS
  The main goal of Twister OS is to provide a true desktop computing experience for single board computers (SBCs), right out-of-the-box. Twister OS includes themes, applications, tools, and optimizations to allow you to get the most out of your SBC.
• Ubuntu
  A complete GNU/Linux-based operating system, freely available with both community and professional support. Ubuntu GNU/Linux is available in both desktop and server editions and supports various computer architectures. Free downloads are available for Ubuntu GNU/Linux.
• Ubuntu flavors
  Ubuntu flavors offer a unique way to experience Ubuntu, each with their own choice of default applications and settings. Ubuntu flavors are owned and developed by members of our global community and backed by the full Ubuntu archive for packages and updates.
• Vanilla OS
  Vanilla OS is designed to be a reliable and productive operating system for your daily work. The desktop environment is perfect for your daily tasks, thanks to its clean and intuitive interface. Everything is setup so that you can start working, and focus on what matters. Vanilla OS is ready to meet your needs whether you are a developer, designer, or student, thanks to a wide range of apps.
• Winux
  No hardware limitations, no absurd requirements. Inspired by Windows 10 and 11, Winux is fast and secure, as a Linux-based operating system should be. Natively supports Windows programs through Wine and Winboat.
• Zorin OS
  Zorin OS Pro brings together the best apps and most advanced features, so you can unleash the full potential of your computer to do your greatest work. It's the ideal choice for power users and creative professionals. Both paid-for Pro and free-of-charge Core versions are available. Zorin OS is the alternative to Windows and macOS designed to make your computer faster, more powerful, secure, and privacy-respecting.

Free support software

• Java
  Java software allows you to run applications called "applets" that are written in the Java programming language. Versions of Java available for Apple macOS, Microsoft Windows and GNU/Linux.
• PuTTY
  A free Telnet/SSH client for Microsoft Windows.

Free website authoring

• Drupal
  Drupal is a free software package that allows an individual or a community of users to easily publish, manage and organize a wide variety of content on a website.
• e107
  A content management system written in PHP and using the popular open source MySQL database system for content storage. It's completely free, totally customisable and in constant development.
• Joomla!
  Joomla! is one of the most powerful Open Source Content Management Systems on the planet. It is used all over the world for everything from simple websites to complex corporate applications.Joomla! is easy to install, simple to manage, and reliable.
• Open Source Web Design
  To put it simply, Open Source Web Design is a collection of web designs submitted by the community that anyone can download free of charge!The Open Source Web Design project was founded in September 2000 by Francis J. Skettino. The goal was to provide the Open Source community with quality web designs to help get people's projects on the web in a way that is both organized and good looking. From personal blogs to content management systems and fully fledged businesses, OSWD has been providing free web designs for years.
• Serendipity
  Serendipity is a PHP-powered weblog application which gives the user an easy way to maintain an online diary, weblog or even a complete homepage. While the default package is designed for the casual blogger, Serendipity offers a flexible, expandable and easy-to-use framework with the power for professional applications.
• TYPO3
  TYPO3 is a free Open Source content management system for enterprise purposes on the web and in intranets. It offers full flexibility and extendability while featuring an accomplished set of ready-made interfaces, functions and modules.
• WordPress
  WordPress is a state-of-the-art publishing platform with a focus on aesthetics, web standards, and usability.

Free web browsers

• Brave
  The new Brave browser blocks ads and trackers that slow you down and invade your privacy. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.
• Google Chrome
  Google Chrome is a browser that combines a minimal design with sophisticated technology to make the web faster, safer, and easier. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.
• Chromium
  Chromium is a free and open-source web browser project, mainly developed and maintained by Google. This codebase provides the vast majority of code for the Google Chrome browser, which is proprietary software and has some additional features. The Chromium codebase is widely used. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.
• Mozilla Firefox
  The award-winning Web browser is better than ever. Faster, safer, and easy to use, Firefox delivers a better Web experience.
• Opera
  Opera delivers robust security and a far-richer feature set than any other Web browser.
• SeaMonkey
  Not just a Web browser but a suite of Internet tools powered by Mozilla, it includes a browser, a client for mail and newsgroups and an HTML editor. Versions are available for Apple macOS, Microsoft Windows and GNU/Linux.

Free virus protection for Mac

• Avira
  Mac malware is now a reality, but the days of worry-free Mac computing are far from over. Install Avira Free Mac Security and postpone the era of Mac viruses.
• ClamXAV
  A free virus checker for Apple macOS.
• Free Sophos antivirus Home Edition
  Protect all the computers in your home with the free Sophos Home.

Free Windows spyware and virus protection

• Advanced SystemCare Free
  Advanced SystemCare Free has a one-click approach to help protect, repair, clean, and optimize your PC. With millions of downloads since 2006, this fantastic, award-winning, free PC repair software is a "must-have" tool for your computer. 100% safe with no adware, spyware, or viruses; a PC maintenance program that's incredibly easy to use.
• AVG Free Edition
  The free version of AVG antivirus for Microsoft Windows.
• Avira AntiVir
  Free antivirus software for private and individual users of Microsoft Windows.
• Free Sophos antivirus Home Edition
  Protect all the computers in your home with the free Sophos Home.

Free virtual machines

• VirtualBox
  VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.

Even more free and open source software

• Christopher Smart's blog
  Just another Linux geek.
• Guru99 tutorials library
  A totally new kind of learning experience.
• Guru99 Kali Linux Tutorial
  Kali Linux is a Security Distribution of Linux specifically designed for digital forensics and penetration testing.