List of free and open-source software packages

This is a list of open-source software 'packages', computer software licensed under free software licenses and open-source licenses. Software that fits the Free Software Definition may be more appropriately called free software; the GNU project in particular objects to their works being referred to as open-source. For more information about the philosophical background for open-source software, see free software movement and Open Source Initiative. However, nearly all software meeting the Free Software Definition also meets the Open Source Definition and vice versa. A small fraction of the software that meets either definition is listed here. Some of the open-source applications are also the basis of commercial products, shown in the List of commercial open-source applications and services.

Artificial intelligence

General AI

OpenCog – project that aims to build an artificial general intelligence framework. OpenCog Prime is a specific set of interacting components designed to give rise to human-equivalent artificial general intelligence.

Large language models

BLOOM – open multilingual language model released in 2022 with 176B parameters
DeepSeek – R1 and V3
DBRX – open source LLM released in March 2024
GPT-J – LLM with 6 billion parameters developed by EleutherAI
GPT-1 – OpenAI LLM released under the MIT License in June 2018
GPT-2 – OpenAI LLM released under the MIT License in November 2019
XLNet – Google LLM released as an open source project in June 2019 under the Apache 2.0 license
BERT – Google LLM released as an open source project in October 2018 under the Apache 2.0 license
T5 – Google LLM released as an open source project in 2019 under the Apache 2.0 license

Computer vision

AForge.NET – computer vision, artificial intelligence and robotics library for the .NET framework
OpenCV – computer vision library in C++

Machine learning

See List of open-source machine learning software
See [|Data Mining] below
See R programming language – packages of statistical learning and analysis tools

Planning

TREX – reactive planning

Robotics

Assistive technology

Speech (synthesis and recognition)

CMU Sphinx – speech recognition software from Carnegie Mellon University
Emacspeak – audio desktop
ESpeak – compact software speech synthesizer for English and other languages
Festival Speech Synthesis System – general multilingual speech synthesis
Audio Recognition Framework – voice, audio, speech NLP processing
NonVisual Desktop Access – screen reader, for Windows
Text2Speech – Text-To-Speech Software

Other assistive technology

Dasher – unique text input software
Gnopernicus – AT suite for GNOME 2
Virtual Magnifying Glass – multi-platform screen magnification tool

CAD

Archimedes (CAD)
Art of Illusion
Blender
BRL-CAD – constructive solid geometry solid modeling computer-aided design system
FreeCAD – parametric 3D CAD modeler with a focus on mechanical engineering, BIM, and product design
LeoCAD
LibreCAD – 2D CAD software using AutoCAD-like interface and file format
MakeHuman
MeshLab
Open Cascade Technology – CAD kernel for 3D CAD, CAM, CAE
OpenSCAD – scripting-based 3D CAD software
QCAD
SolveSpace – 2D and 3D CAD, constraint-based parametric modeler with simple mechanical simulation abilities
Sweet Home 3D
Wings 3D

Computer-aided engineering (CAE)

Computer-aided manufacturing (CAM)

Subtractive">Subtractive manufacturing">Subtractive

LinuxCNC
FreeCAD –

[Additive Manufacturing]

Electronic design automation (EDA)

Electric
FreePCB
Fritzing – CAD software for the design of electronics hardware to build more permanent circuits from prototypes
gEDA
GNU Circuit Analysis Package
Icarus Verilog
KiCad – suite for electronic design automation for schematic capture, PCB layout, manufacturing file viewing, SPICE simulation, and engineering calculation
KTechLab
Magic
Ngspice
pcb-rnd
Oregano
Quite Universal Circuit Simulator
Verilator
XCircuit

Computer simulation

Blender – 3D computer graphics software toolset used for creating animated films, visual effects, art, 3D printed models, and motion graphics
FreeCad – equivalent of Blender, towards to mechanical engineering
OpenFOAM – software used for computational fluid dynamics
FlightGear - atmospheric and orbital flight simulator with a flight dynamics engine that was used in a 2015 NASA benchmark to judge new simulation code to space industry standards
SimPy – queue-theoretic event-based simulator written in Python
Salome – generic platform for Pre- and Post-Processing for numerical simulation

[Cypherpunk] software

Cryptography and Privacy Software

OpenPGP – open-source version of Pretty Good Privacy
GNU Privacy Guard – replacement for PGP
OpenSSL – library for applications that provide secure communications over computer networks
NaCl (software) – crypto library
Libsodium – fork of NaCl
VeraCrypt – disk encryption software forked from TrueCrypt
LUKS – standard for disk encryption on Linux systems
Nym (mixnet) - mix network that uses noise and random packet timing for obfsucation, overlay network for NymVPN
Tor (network) – free overlay network for enabling anonymous communication
Tails (operating system) – security-focused Linux distro using Tor by default
Signal (software) – secure messaging app
Off-the-Record Messaging – protocol for secure instant messaging
GPGTools – macOS suite for GnuPG-based encryption

Hacking and Network Security Tools

Aircrack-ng – Wi-Fi security auditing tool
BackTrack – predecessor to Kali Linux
Burp Suite Community Edition – security assessment and penetration testing of web applications
Ghidra – software reverse engineering suite developed by the NSA
Hashcat – password recovery utility
High Orbit Ion Cannon - Ddos
Hydra (software) – login cracker supporting numerous protocols
John the Ripper – password cracking tool
Kali Linux – penetration testing Linux distribution
Metasploit Project – framework for developing and executing exploit code
Netcat – network utility for reading/writing data across networks
Nikto (vulnerability scanner) – web server vulnerability scanner
Nmap – network scanning, port scanner, and auditing tool
OpenSSH – implementation of the SSH protocol
Radare2 – reverse engineering framework
Snort (software) – network intrusion detection system
sqlmap – automated SQL injection and database takeover tool
Suricata (software) – network threat detection engine
Volatility (memory forensics) – memory forensics framework for incident response
Wireshark – network protocol analyzer
YARA – tool to identify and classify malware

Decentralized and Anonymous Communication Projects

Freenet – peer-to-peer platform for censorship-resistant communication
Bitmessage – encrypted peer-to-peer messaging protocol
I2P – anonymous network layer for secure communication
Nym Technologies - privacy- and security-focused VPN service
Tor (network) – free overlay network for enabling anonymous communication

Decentralized File Sharing and Storage

qBittorrent – BitTorrent client
Transmission (BitTorrent client) – lightweight BitTorrent client
IPFS – InterPlanetary File System for decentralized storage and sharing
RetroShare – secure communication platform with file sharing

Cryptocurrencies and Anonymous Finance

Zerocoin – privacy-focused cryptocurrency protocol
Zcash – cryptocurrency based on Zerocoin using zk-SNARKs
Monero – privacy-focused cryptocurrency using ring signatures
NYM) — Nym mixnet privacy- and security-focused token

Cybersecurity

Antivirus

ClamAV – cross-platform antimalware toolkit written in C and C++, able to detect many types of malware including viruses
ClamWin – antivirus tool for Windows and written in C, C++
Lynis – security audit tool for Unix and Linux

Data loss prevention

MyDLP not updated since 2014

Data recovery

Forensics

Disk erasing

Encryption

Disk encryption

Firewall

Network and security monitoring

Snort – network intrusion detection system and intrusion prevention system
OpenVAS – software framework of several services and tools offering vulnerability scanning and vulnerability management

Secure Shell (SSH)

Cyberduck – macOS and Windows client
Lsh – server and client, with support for SRP and Kerberos authentication
OpenSSH – client and server
PuTTY – client-only

Password management

Bitwarden
KeePass
KeePassXC – multiplatform fork able to open KeePass databases
Password Safe
Mitro
Pass
Proton Pass

Data storage and management

Disk cleaning utilities

BleachBit

Database management systems (including administration)

Apache Cassandra – NoSQL database from Apache Software Foundation offers support for clusters spanning multiple datacenter
Apache CouchDB – NoSQL database from Apache Software Foundation with multi-master replication
MariaDB – community-developed relational database management system with pluggable storage engines and commercial support
PostGIS – adds support for geographic objects to the PostgreSQL as per Open Geospatial Consortium
PostgreSQL – relational database management system emphasizes on extensibility and SQL compliance and available for Windows, Linux, FreeBSD, and OpenBSD

Data mining

Environment for DeveLoping KDD-Applications Supported by Index-Structures – data mining software framework written in Java with a focus on clustering and outlier detection methods
FrontlineSMS – information distribution and collecting via text messaging
Konstanz Information Miner (KNIME)
OpenNN – neural network software library written in C++
Orange (software) – data visualization and data mining for novice and experts, through visual programming or Python scripting. Extensions for bioinformatics and text mining
RapidMiner – data mining software written in Java, fully integrating Weka, featuring 350+ operators for preprocessing, machine learning, visualization, etc. – the prior version is available as open-source
Scriptella ETL – ETL (Extract-Transform-Load) and script execution tool. Supports integration with J2EE and Spring. Provides connectors to CSV, LDAP, XML, JDBC/ODBC, and other data sources
Weka – data mining software written in Java featuring machine learning operators for classification, regression, and clustering
JasperSoft – data mining with programmable abstraction layer

Data Visualization Components

ParaView – plotting and visualization functions developed by Sandia National Laboratory; capable of massively parallel flow visualization utilizing multiple computer processors
VTK – toolkit for 3D computer graphics, image processing, and visualisation

Disk partitioning software

Enterprise search engines

ETLs (Extract Transform Load)

File archivers

File systems

OpenAFS – distributed file system supporting a very wide variety of operating systems
Tahoe-LAFS – distributed file system/Cloud storage system with integrated privacy and security features
CephFS – distributed file system included in the Ceph storage platform

Desktop publishing

Collabora Online Draw and Writer – edition of LibreOffice accessible from a web browser
Scribus – designed for layout, typesetting, and preparation of files for professional-quality image-setting equipment. It can also create animated and interactive PDF presentations and forms
LyX – "What You See Is What You Mean" document creation system, LyX makes use of the LaTeX markup macro system for TeX, allowing the elegant creation of documents which match up with the layouts in it for various document classes

E-book management and editing

Calibre – cross-platform suite of ebook software
Collabora Online Writer – edition of LibreOffice accessible from a web browser
Sigil – editing software for e-books in the EPUB format

Education

E-learning, learning support

ATutor – web-based Learning Content Management System
Canvas LMS – web-based, open, extensible learning management system
Chamilo – web-based e-learning and content management system
Claroline – collaborative Learning Management System
DoceboLMS – SAAS/cloud platform for learning
eFront – icon-based learning management system
H5P – framework for creating and sharing interactive HTML5 content
IUP Portfolio – educational platform for Swedish schools
ILIAS – web-based learning management system
Moodle – learning management system
OLAT – web-based Learning Content Management System
Omeka – content management system for online digital collections
Sakai Project – web-based learning management system
SWAD – web-based learning management system

Academic advising

FlightPath – academic advising software for universities

Educational suites for children

Tux Paint – painting application for 3–12 year olds
GCompris – educational entertainment, aimed at children aged 2–10

Language

Operating systems

Mind mapping & others

Vym (software)
Compendium (software)
Gnaural – brainwave entrainment software

Offline learning & Open data

Kiwix – offline web browser that allows users download Wikipedia entire content and use for offline learning, later was expanded with repositories for Wikimedia Foundation, public domain texts from Project Gutenberg, many of the Stack Exchange sites, and other resources
OpenStreetMap – OpenStreetMap was developed in 2004, it uses Open data and users data input through Crowdsourcing and Web mapping to create a complete and downloadable alternative to other online maps, this allow users to enter data when there is no data available due to lack of governance and economic interest or due lower population of the places mapped

Typing

KTouch – touch typing lessons with a variety of keyboard layouts
Tux Typing – typing tutor for children, featuring two games to improve typing speed

Engineering

Advanced Simulation Library
ASCEND
Calcpad
Calculix
CHEMKIN – chemical kinetics
COCO simulator – chemical process simulator
CP2K – quantum chemistry and solid-state physics
DWSIM – chemical process simulator
General Mission Analysis Tool – space mission analysis
GNU Octave – numerical-analysis
GROMACS – simulations of proteins, lipids, and nucleic acids
JSBSim – flight dynamics engine
LAMMPS – Molecular dynamics
Open Babel – chemical informatics
OpenModelica – chemical process simulator
OpenSees – earthquake engineering
OpenVSP – parametric aircraft geometry tool
Pyomo – mathematical optimization
REFPROP – reference Fluid Thermodynamic and Transport Properties
XFOIL – analysis of subsonic isolated airfoils

File formats

2D

Video

Audio

Document & Text

.adoc – AsciiDoc
.epub – ebook format
.latex –, macro package built on top of TeX for simplification
.md – Markdown
.odt – OpenDocument
.rtf – Rich Text Format
.tex – high-quality typography for mathematical notation, physics, chemistry, engineering/scientific notation
.texinfo

Web and Interactive Media

.css – Cascading Style Sheets
.html – HyperText Markup Language
.json – GeoJSON, JSON-LD, JSON-RPC, JsonML, Smile, UBJSON
.mml – MathML

Database & Data Storage

.avro – Apache Avro
.cml – Chemical Markup Language
.csv – Comma-separated values
.hdf5 – Hierarchical Data Format
.ods – OpenDocument Spreadsheet
.orc – Apache ORC
.parquet – Apache Parquet
.protobuf – Protocol Buffers developed by Google
.shp – Shapefile
.sqlite – SQLite
.tsv – Tab-separated values
.xml – Extensible Markup Language

Finance

Accounting

1DayLater – invoicing software
GnuCash – double-entry book-keeping
HomeBank – personal accounting software
KMyMoney – double-entry book-keeping
LedgerSMB – double-entry book-keeping
RCA open-source application – management accounting application
SQL-Ledger – double-entry book-keeping
TurboCASH – double-entry book-keeping for Windows

Cryptocurrency

Bitcoin – blockchain platform, peer-to-peer decentralised digital currency
Ethereum – blockchain platform with smart contract functionality

CRM

CiviCRM – Constituent Relationship Management software aimed at charities and NGOs
iDempiere – business Suite, ERP and CRM
SuiteCRM – web-based CRM

ERP

Adempiere – Enterprise resource planning business suite
Apache OFBiz – suite of enterprise applications from Apache Software Foundation
Compiere – ERP solution automates accounting, supply chain, inventory, and sales orders
Dolibarr – web-based ERP system
ERPNext – web-based ERP system for managing accounting and finance
ERP5 – Single Unified Business Model based system written with Python and Zope
iDempiere – fully navigable on PCs, tablets and smartphones driven only by a community of supporters
JFire – ERP business suite written with Java and JDO
LedgerSMB – double entry accounting and ERP system written with Perl
metasfresh – ERP Software
Odoo – ERP, CRM and CMS
Openbravo – web-based ERP
Tryton – ERP

Human resources

OrangeHRM – commercial human resource management

Microfinance

Mifos – microfinance Institution management software

Process management

Bonita Open Solution – Business Process Management

Games

Game engines

Physics engines

Shader languages

Action

Nexuiz – first-person shooter

OpenArena – first-person shooterRed Eclipse – first-person shooterTremulous – first-person shooterUnvanquished – First-person shooter
Xonotic – first-person shooter that runs on a heavily modified version of the Quake engine known as the DarkPlaces engine
Warsow – first-person shooter fast-paced arena FPS game that runs on the Qfusion engine

Application layer

WINE – allows Windows applications to be run on Unix-like operating systems

Chess

Educational games

GCompris – software suite comprising educational entertainment software for children aged 2 to 10
Tux, of Math Command
Tux Paint

Video game emulation

MAME – multi-platform emulator for arcade game systems
MESS – multi-platform emulator
RetroArch – cross-platform front-end for emulators, game engines and video games
Snes9x – Super Nintendo emulator
Stella – Atari 2600 emulator
PCSX – PlayStation emulator
PCSX2 – PlayStation 2 emulator
PPSSPP – PlayStation Portable emulator
Project64 – Nintendo 64 emulator
RetroArch – emulator and media player frontend
RPCS3 – PlayStation 3 emulator
Dolphin (emulator) – GameCube and Wii emulator
Citra (emulator) – Nintendo 3DS and Wii emulator
Cemu – Wii U emulator
TIC-80 – virtual machine game engine that mimics the 8-bit systems of the 1980s

Music video games

Frets on Fire

Karaoke

UltraStar

Rhythm game

StepMania

Puzzle

Pingus – Lemmings alternative with penguins instead of lemmings

Sandbox

Luanti – voxel game engine

Snake games

GLtron

Simulation

Endless Sky – space trading and combat simulation
FlightGear – flight simulator
OpenTTD – business simulation game in which players try to earn money via transporting passengers and freight by road, rail, water and air
SuperTuxKart – kart racing game that features mascots of various open-source projects

Strategy

0 A.D. – real-time strategy video game
Freeciv – turn-based strategy game inspired by proprietary Sid Meier's Civilization series
Glest
The Battle for Wesnoth – turn-based strategy video game with fantasy setting

Genealogy

Gramps (software) – genealogy software

Geographic information systems

QGIS – cross-platform desktop geographic information system application to view, edit, and analyse geospatial data

Integrated library management software

Evergreen – integrated Library System initially developed for the Georgia Public Library Service's PINES catalog
FOLIO - Modular, open-source library services platform
Koha – SQL-based library management
NewGenLib
OpenBiblio
PMB
refbase – web-based institutional repository and reference management software

Image editor

Darktable – digital image workflow management, including RAW photo processing
digiKam – integrated photography toolkit including editing abilities
GIMP – raster graphics editor aimed at image retouching/editing
Hugin – panorama stitching
Inkscape – vector graphics editor
Karbon – scalable vector drawing application in KDE
Krita – digital painting, sketching and 2D animation application, with a variety of brush engines
LazPaint – raster and vector graphics editor, aimed at being simpler to use than GIMP
LightZone – digital photo editor software application
Luminance HDR – high dynamic range images
RawTherapee – digital image workflow management aimed at RAW photo processing

Maps & navigation

OpenStreetMap – open geographic database updated and maintained by a community of volunteers via open collaboration
OsmAnd – freemium maps & navigation Android and iOS app
Organic Maps – offline map and navigation app for Android & iOS
CoMaps

Mathematics

Computer algebra systems

Physics

[Computational electromagnetics]

[Computational fluid dynamics]

[Computational particle physics]

[Computational astrophysics]

[Monte Carlo method]

Symbolic manipulation systems

FORM (symbolic manipulation system)

Statistics

R – statistics software

Numerical analysis

Octave – numerical analysis software
Scilab – numerical analysis software

Geometry

Geogebra – geometry and algebra
R.
CaRMetal
DrGeo
Kig
KSEG

Plotting software">Plot (graphics)">Plotting software

Charting

Mathematical notation software

Mathematical art software

Spreadsheet

Collabora Online Calc – spreadsheet component of the Collabora Online package
LibreOffice Calc – spreadsheet component of the LibreOffice package
OnlyOffice Spreadsheets – spreadsheet software of OnlyOffice suite
Gnumeric – spreadsheet program of the GNOME Project
Calligra Sheets – spreadsheet component of the Calligra Suite in KDE
Proton Sheets - spreadsheet component of office suite and Drive
Pyspread – spreadsheet which uses Python for macro programming, and allows each cell to contain data, the results of a calculation, a Python program, or the results of a Python program

Mobile software

Celestia
Calligra
Collabora Office
CoMaps
Conversations
F-Droid – app store and software repository
I2P – anonymous network layer that allows for censorship-resistant, peer-to-peer communication
Kiwix – offline web browser that allows users to download the entire content of Wikipedia for offline learning purposes.
Krita
Linphone
Monal
NetHunter App Store – fork of F-Droid for Kali NetHunter
OsmAnd – freemium maps & navigation Android and iOS app
OpenVPN – virtual private network system that implements techniques to create secure point-to-point or site-to-site connections in routed or bridged configurations and remote access facilities. It implements both client and server applications
Orbot – free proxy app that provides anonymity on the Internet for users of the Android and iOS operating systems. It allows traffic from apps such as web browsers, email clients, map programs, and others to be routed via the Tor network
Organic Maps – offline map and navigation app for Android & iOS
Quicksy
Tor Browser – onion-routed browser by The Tor Project, based on Firefox ESR
VLC
Wikipedia – See also: List of Wikipedia mobile applications

Media

Audio editors, audio management

Audacity
Ardour – professional digital audio workstation
LMMS – digital audio workstation

CD/USB-writing software

Flash animation

Pencil2D – for animations
SWFTools – for scripting

Game engines

Blender Game Engine – discontinued 2019
Godot – application for the design of cross-platform video games
MonoGame – C# framework
Open3DEngine – based on Amazon Lumberyard
Stride – 2D and 3D cross-platform game engine originally developed by Silicon Studio

Chess engines

Graphics

2D

Pencil2D – simple 2D graphics and animation program
Synfig – 2D vector graphics and timeline based animation
TupiTube – application for the design and creation of animation
OpenToonz – part of a family of 2D animation software
Krita – digital painting, sketching and 2D animation application, with a variety of brush engines
Blender – computer graphics software, Blender's Grease Pencil tools allow for 2D animation within a full 3D pipeline
mtPaint – raster graphics editor for creating icons, pixel art

3D

Blender – computer graphics software featuring modeling, sculpting, texturing, rigging, simulation, rendering, camera tracking, video editing, and compositing
FreeCAD
MakeHuman
OpenFX – modeling and animation software with a variety of built-in post processing effects
Picogen – terrain generator
Seamless3d – node-driven 3D modeling software
Wings 3D – subdivision modeler inspired by Nendo and Mirai from Izware

3D rendering

Image galleries

Image viewers

Maps

Subtitle

Video converters

Video editing

DVD authoring

Screencast

recordMyDesktop
Open Broadcaster Software – cross-platform streaming and recording program

Other media packages

Celtx – media pre-production software

Ripping

Video encoders

Video players

Networking and Internet

Advertising

Revive Adserver

Communication-related

Asterisk – telephony and VoIP server
Ekiga – video conferencing application for GNOME and Microsoft Windows
ConferenceXP – video conferencing application for Windows XP or later
Dino – xmpp client, supporting both OMEMO encryption and Jingle Audio/Video protocol, under Windows, Linux and BSD
FreePBX – front-end and advanced PBX configuration for Asterisk
FreeSWITCH – telephony platform
Gajim – xmpp client
Jami – cross-platform, peer to peer instant-messaging and video-calling protocol that offers end-to-end encryption and SIP client
Jitsi – Java VoIP and Instant Messaging client
QuteCom – voice, video, and IM client application
Enterprise Communications System sipXecs – SIP Communications Server
Telegram
Twinkle – VoIP softphone
Tox – cross-platform, peer-to-peer instant-messaging and video-calling protocol that offers end-to-end encryption

E-mail

Amavis – email content filter
Claws Mail – email Client
Fetchmail – email Retrieval
Geary – email client based on WebKitGTK+
GNUMail – cross-platform email client
Hula – discontinued mail and calendar project
K-9 Mail – Android Email Client
MailScanner – email security system
MH Message Handling System – email Client
Modest – email Client
Mozilla Mail & Newsgroups – email Client that was part of the now discontinued Mozilla Application Suite
Mozilla Thunderbird – email, news, RSS, and chat client
POPFile – cross-platform mail filter
Proton Mail - app and web-based end-to-end encrypted e-mail evolved to become FOSS
Roundcube – web-based IMAP email client
Sylpheed – email and News Client
Sympa – MLA software

File transfer

Grid and distributed processing

Middleware

Apache Axis2 – Web service framework
Apache Geronimo – application server
Bonita Open Solution – J2EE web application and java BPMN2 compliant engine
GlassFish – application server
Apache Tomcat – servlet container and standalone webserver
JBoss – application server
OpenRemote – IoT Middleware
TAO (software) – C++ implementation of the OMG's CORBA standard
Enduro/X – C/C++ middleware platform based on X/Open group's XATMI and XA standards

RSS, Atom readers, aggregators

Akregator – platforms running KDE
Liferea – platforms running GNOME
NetNewsWire – macOS, iOS
RSS Bandit – Windows, using .NET framework
RSSOwl – Windows, macOS, Solaris, Linux using Java SWT Eclipse

Social network

Bluesky - microblogging platform similar to Twitter utilizing the AT Protocol
Mastodon - platform for decentralized social networking with microblogging features
Nostr - open protocol for decentralized message transmission, with the intention to be able to resist internet censorship while maintaining session integrity.

Peer-to-peer file sharing

I2P – anonymous network layer that allows for censorship-resistant, peer-to-peer communication
OnionShare – file sharing app using Tor network
Popcorn Time – multi-platform media player
qBittorrent – BitTorrent client
Transmission – BitTorrent client
Deluge – BitTorrent client

Portal Server

Remote access and management

Web browsers

Graphical

Chromium – web browser using the custom Blink engine from which Google Chrome draws its source code
Brave – privacy-focused web browser based on Chromium browser
Falkon – web browser based on Blink engine, a KDE project
Firefox – Mozilla-developed web browser using Gecko layout engine
Mullvad Browser - privacy-focused browser codeveloped with primary developer Tor Project and distributed by Mullvad
Waterfox – Firefox fork supporting legacy extensions, 64-bit only
Pale Moon – customizable fork of Firefox
Tor Browser – onion-routed browser by The Tor Project, based on Firefox ESR
GNOME Web – WebKit-based web browser for the GNOME desktop environment
Midori – web browser using the WebKit layout engine
qutebrowser – keyboard operated Webkit-based browser with vi-like keybindings
SeaMonkey Navigator – the SeaMonkey internet suite's web browser
Surf – minimal tab-less browser by suckless.org using WebKitGTK
Firefox Focus – privacy-focused mobile web browser from Mozilla available for Android and iOS

Text-based

Lynx – text-based web browser developed since 1992
Links – text-based browser with a framebuffer-based graphical mode
ELinks – fork of Links with JavaScript support

Webcam

Cheese – GNOME webcam application
Guvcview – Linux webcam application

Webgrabber

Web-related

Apache Cocoon – web application framework
Apache Tomcat
Apache – web server
AWStats – log file parser and analyzer
BookmarkSync – tool for browsers
Caddy – extensible, cross-platform, web server written in Go.
Cherokee – HTTP server
curl-loader – HTTP/HTTPS/FTP/FTPS loading and testing tool
Docker – Docker Engine is open-source for Linux only
FileZilla – FTP
H2O – supports HTTP/2, TLS, and server push
Hiawatha – HTTP server
HTTP File Server – file server software, with a drag-and-drop interface
lighttpd – HTTP Server
Lucee – CFML application server
Nginx – web server/reverse proxy and e-mail proxy
NetKernel – Internet application server
Qcodo – PHP5 framework
Squid – web proxy cache
thttpd – designed for simplicity, small memory footprint, and speed
Vaadin – Java-based framework for creating web applications
Varnish – web application accelerator/reverse proxy and load balancer/HTTP router
XAMPP – package of web applications including Apache and MariaDB
Zope – web application server

Web search engines

SearXNG – self-hostable metasearch engine
YaCy – P2P-based search engine

Other networking programs

JXplorer – LDAP client
Nextcloud – fork of ownCloud
OpenLDAP – LDAP server
ownCloud – file share and sync server
Wireshark – network monitor

Office software

Office suites

Apache OpenOffice – the cross platform office productivity suite from Apache Software Foundation consists of programs for word processing, spreadsheets, presentation, diagrams and drawings, databases, etc.
Calligra Suite – the office productivity suite from KDE consists of programs for word processing, spreadsheets, presentation, databases, vector graphics, and digital painting
Collabora Online – edition of LibreOffice, web application, mobile phone, tablet, Chromebook and desktop
LibreOffice – the cross platform office productivity suite from The Document Foundation consists of programs for word processing, spreadsheets, presentation, diagrams and drawings, databases, etc.
OnlyOffice Desktop Editors – offline edition of the Cloud

PDF editors

PDFsam Basic edition – platform independent software designed to split, merge, mix, extract pages and rotate PDF files for Windows, Linux, MacOS. Open-source version of their commercial offering

Operating systems

Be advised that available distributions of these systems can contain, or offer to build and install, added software that is neither free software nor open-source.

BSD – FreeBSD, OpenBSD, NetBSD, GhostBSD, TrueNAS, MidnightBSD, DragonFly BSD, OPNsense, pfSense, XigmaNAS, among others.
GrapheneOS
Kali NetHunter
Linux – Debian, Ubuntu, Manjaro, Fedora, openSUSE, antiX, NixOS, Kali, Alpine, Tails, Mageia, Slackware, Gentoo, BlackArch, among others.
LineageOS – android-based operative system for tablets and mobile phones
GNU Hurd
Mobian
Plasma Mobile
PostmarketOS
PureOS
Ubuntu Touch
Redox OS
FreeDOS – OS compatible with IBM PC DOS and Microsoft's MS-DOS
ReactOS – OS intended to run the same software as Windows, originally designed to simulate Windows NT 4.0, later aiming at Windows 7 compatibility. It has been in the development stage since 1996.

Emulation and Virtualization

AppleWin
DOSBox – DOS programs emulator
GNOME Boxes
Hercules (emulator)
Kernel-based Virtual Machine
QEMU
VirtualBox – hosted hypervisor for x86 virtualization

Personal information managers

Chandler – developed by the Open Source Applications Foundation
KAddressBook
Kontact
KOrganizer
Mozilla Calendar – Mozilla-based, multi-platform calendar program
GNOME Evolution
Perkeep – personal data store for pictures
Project.net – commercial project management
TeamLab – platform for project management and collaboration

Programming language support

Programming languages

Compilers and assemblers

Bug trackers

Code generators

Babel – JavaScript transcompiler
Bison
CodeSynthesis XSD – XML Data Binding compiler for C++
CodeSynthesis XSD/e – validating XML parser/serializer and C++ XML Data Binding generator for mobile and embedded systems
Flex lexical analyser – generates lexical analyzers
Open Scene Graph – 3D graphics application programming interface
OpenSCDP – Open Smart Card Development Platform
SableCC – parser generator for Java and .NET
SWIG – Simplified Wrapper and Interface Generator for several languages
xmlbeansxx – XML Data Binding code generator for C++
YAKINDU Statechart Tools – Statechart code generator for C++ and Java

Documentation generators

Doxygen – tool for writing software reference documentation. The documentation is written within code
Mkd – extracts software documentation from source code files, pseudocode, or comments
Natural Docs

Configuration software

Debuggers (for testing and trouble-shooting)

GNU Debugger – portable debugger that runs on many Unix-like systems
Memtest86 – stress-tests RAM on x86 machines
Xnee – record and replay tests

Risk management

Active Agenda – operational risk management and rapid application development platform

Science

Bioinformatics

Computational chemistry

Molecular dynamics

Molecular modeling

Cheminformatics & docking

Utilities / frameworks

Data science

Apache Flink – stream and batch data processing framework
Apache Hadoop – distributed storage and processing framework
Apache Mahout – scalable machine learning library
Apache Spark – unified analytics engine
Dask – parallel computing for analytics in Python
ELKI – data analysis algorithms library
GNU Octave – numerical computing environment
JASP – GUI program for data analytics, data science, and machine learning
Jupyter Notebook – interactive computing
Keras – neural network library
KNIME – data analytics platform
Matplotlib – data visualization library
MLlib – machine learning library for Apache Spark
NumPy – numerical computing library
Orange – data mining tool
pandas – data manipulation library
PyTorch – machine learning and deep learning framework
Python
R – statistical computing language
SageMath – mathematics and data analysis environment
SciPy – scientific computing library
scikit-learn – Python machine learning library
TensorFlow – machine learning framework
WEKA – machine learning and data analysis suite

Electronic lab notebooks

Jupyter

Microscope image processing

CellProfiler – automatic microscopic analysis, aimed at individuals lacking training in computer vision
Endrov – Java-based plugin architecture designed to analyse complex spatio-temporal image data
Fiji – imageJ-based image processing
Gwyddion – scanning probe microscopy data visualization and processing
Ilastik – image-classification and segmentation software
ImageJ – image processing application developed at the National Institutes of Health
IMOD – 2D and 3D analysis of electron microscopy data
ITK – development framework used for creation of image segmentation and registration programs
KNIME – data analytics, reporting, and integration platform
VTK – C++ toolkit for 3D computer graphics, image processing, and visualisation
3DSlicer – medical image analysis and visualisation

Molecular design software

Molecular dynamics

GROMACS – protein, lipid, and nucleic acid simulation
LAMMPS – molecular dynamics software
MDynaMix – general-purpose molecular dynamics, simulating mixtures of molecules
ms2 – molecular dynamics and Monte Carlo simulation package to predict thermophysical properties of fluids
NWChem – wuantum chemical and molecular dynamics software

Molecule editors

Molecular graphics systems

Molecular mechanics modeling

[Molecular structure]

Molecule viewer

Avogadro – plugin-extensible molecule visualisation
BALLView – molecular modeling and visualisation
Jmol – 3D representation of molecules in many formats, for teaching use
Molekel – molecule viewing software
MeshLab – able to import PDB dataset and build up surfaces from them
PyMOL – high-quality representations of small molecules and biological macromolecules
QuteMol – interactive molecule representations offering an array of innovative OpenGL visual effects
RasMol – visualizes biological macromolecules

Nanotechnology

nanoHUB
Ninithi – visualise and analyse carbon allotropes, such as carbon nanotube, Fullerene, graphene nanoribbons

Nuclear Fusion Engineering

OpenMC

Plotting

Veusz

Quantum chemistry

CP2K – atomistic and molecular simulation of solid-state, liquid, molecular, and biological systems

Screensavers

Simulation software

List of free and open source simulation software

Statistics

R – statistics software
LimeSurvey – online survey system

Theology

Bible study tools

Go Bible – free Bible viewer application for Java mobile phones
Marcion – Coptic–English/Czech dictionary
OpenLP – worship presentation program licensed under the GNU General Public License
The SWORD Project – CrossWire Bible Society's free software project

List of free and open-source software packages

Artificial intelligence

General AI

Large language models

Computer vision

Machine learning

Planning

Robotics

Assistive technology

Speech (synthesis and recognition)

Other assistive technology

CAD

Computer-aided engineering (CAE)

Computer-aided manufacturing (CAM)

Subtractive">Subtractive manufacturing">Subtractive

[Additive Manufacturing]

Electronic design automation (EDA)

Computer simulation

[Cypherpunk] software

Cryptography and Privacy Software

Hacking and Network Security Tools

Decentralized and Anonymous Communication Projects

Decentralized File Sharing and Storage

Cryptocurrencies and Anonymous Finance

Cybersecurity

Antivirus

Data loss prevention

Data recovery

Forensics

Anti-forensics

Disk erasing

Encryption

Disk encryption

Firewall

Network and security monitoring

Secure Shell (SSH)

Password management

Data storage and management

Disk cleaning utilities

Database management systems (including administration)

Data mining

Data Visualization Components

Disk partitioning software

Enterprise search engines

ETLs (Extract Transform Load)

File archivers

File systems

Desktop publishing

E-book management and editing

Education

E-learning, learning support

Academic advising

Educational suites for children

Language

Operating systems

Mind mapping & others

Offline learning & Open data

Typing

Engineering

File formats

2D

Raster">Raster graphics">Raster imagery

Vector">Vector graphics">Vector imagery

3D

Video

Audio

Document & Text

Web and Interactive Media

Database & Data Storage

Finance

Accounting

Cryptocurrency

CRM

ERP

Human resources

Microfinance

Process management

Games

Game engines

Physics engines