Free software programmed in C

general-purpose programming language

PHP is a general-purpose scripting language geared towards web development. It was created by Danish-Canadian programmer Rasmus Lerdorf in 1993 and released in 1995. The PHP reference implementation is now produced by the PHP Group. PHP was originally an abbreviation of Personal Home Page, but it now stands for the recursive backronym PHP: Hypertext Preprocessor.

Perl is a high-level, general-purpose, interpreted, dynamic programming language. Though Perl is not officially an acronym, there are various backronyms in use, including "Practical Extraction and Reporting Language".

general-purpose programming language

Lua is a lightweight, high-level, multi-paradigm programming language designed mainly for embedded use in applications. Lua is cross-platform software, since the interpreter of compiled bytecode is written in ANSI C, and Lua has a relatively simple C application programming interface (API) to embed it into applications.

free and open-source 3D computer graphics software

The GNU Image Manipulation Program, commonly known by its acronym GIMP ( ; always stylized in capitals; formerly, The GIMP), is a free and open-source raster graphics editor.

Git () is a distributed version control software system that is capable of managing versions of source code or data. It is often used to control source code by programmers who are developing software collaboratively.

GNOME () is a free and open-source desktop environment for Linux and other Unix-like operating systems. It is distributed as the default desktop environment of many major Linux distributions, including Debian, Fedora Linux, Ubuntu, Red Hat Enterprise Linux, and SUSE Linux Enterprise, and is the default in Oracle Solaris, a Unix operating system.

free, open-source reimplementation of the AT&T UNIX operating system

open-source web server software

daemon and utilities for an anonymizing network

text editor, improved version of Vi

Unix-like operating system kernel, basis for all Linux operating systems

OpenBSD is a security-focused, free software, Unix-like operating system based on the Berkeley Software Distribution (BSD). Theo de Raadt created OpenBSD in 1995 by forking NetBSD 1.0. The OpenBSD project emphasizes portability, standardization, correctness, proactive security, and integrated cryptography.

GNU Project implementation of the standard Unix shell

PostgreSQL ( ), also known as Postgres, is a free and open-source relational database management system (RDBMS) emphasizing extensibility and SQL compliance. PostgreSQL features transactions with atomicity, consistency, isolation, durability (ACID) properties, automatically updatable views, materialized views, triggers, foreign keys, and stored procedures. It is supported on all major operating systems, including Windows, Linux, macOS, FreeBSD, and OpenBSD, and handles a range of workloads from single machines to data warehouses, data lakes, or web services with many concurrent users.

advanced version control system

multi-platform open-source digital audio recording and editing application

alt=Screenshot of Multics Emacs|thumb|Multics Emacs is an example of early Emacs implementations Emacs (), originally named EMACS (an acronym for "Editor Macros"), is a family of text editors that are characterized by their extensibility. The manual for the most widely used variant, GNU Emacs, describes it as "the extensible, customizable, self-documenting, real-time display editor". Development of the first Emacs began in the mid-1970s, and work on GNU Emacs, directly descended from the original, is ongoing; its latest version is , released .

graphical multi-protocol instant messaging client

GTK (formerly GIMP ToolKit and GTK+) is a free open-source widget toolkit for creating graphical user interfaces (GUIs) targeted at Linux and specifically GNOME (though with some use in other desktop environments). It is licensed under the terms of the GNU LGPL, allowing both free and proprietary software to use it.

compatibility layer for running Windows software on Unix-like systems

thumb|ReactOS 0.4.14 running the Firefox [[web browser]] ReactOS is a free and open-source operating system for i586/amd64 personal computers that is intended to be binary-compatible with computer programs and device drivers developed for Windows Server 2003 and later versions of Microsoft Windows. ReactOS has been noted as a potential open-source drop-in replacement for Windows and has been of interest for its information on undocumented Windows APIs.

7-Zip is a free and open-source file archiver, a utility used to place groups of files within compressed containers known as "archives". It is developed by Igor Pavlov and was first released in 1999. 7-Zip has its own archive format called 7z introduced in 2001, but can read and write several others.

scripting language

FreeDOS (formerly PD-DOS) is a free software operating system for IBM PC compatible computers. It intends to provide a complete MS-DOS-compatible environment for running legacy software and supporting embedded systems. FreeDOS can be booted from a floppy disk or USB flash drive and is designed to run well under virtualization or x86 emulation.

Nginx (pronounced "engine x" , stylized as NGINX or nginx) is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache. The software was created by Russian developer Igor Sysoev and publicly released in 2004. Nginx is free and open-source software, released under the terms of the 2-clause BSD license. A large fraction of web servers use Nginx, often as a load balancer.

gedit ( or ) is a text editor designed for the GNOME desktop environment. It was GNOME's default text editor and part of the GNOME Core Applications until GNOME version 42 in March 2022, which changed the default text editor to GNOME Text Editor. Designed as a general-purpose text editor, gedit emphasizes simplicity and ease of use, with a clean and simple GUI, according to the philosophy of the GNOME project. It includes tools for editing source code and structured text such as markup languages. It is free and open-source software under the GNU General Public License version 2 or later.

Wireshark is free and open-source packet analyzer software. It is used for computer network analysis and troubleshooting, software and communications protocol development, and education. Originally named Ethereal, the project was renamed Wireshark in May 2006 due to trademark issues.

web browser, text-based

Cygwin ( ) is a free and open-source Unix-like environment and command-line interface (CLI) for Microsoft Windows. The project also provides a software repository containing open-source packages. Cygwin allows source code for Unix-like operating systems to be compiled and run on Windows. Cygwin provides native integration of Windows-based applications.

free software re-implementation of the SMB networking protocol

MPlayer is a free and open-source media player software application. It is available for Linux, OS X and Microsoft Windows. Versions for legacy systems such as OS/2 and AmigaOS were previously available, but are no longer actively maintained. A port for DOS using DJGPP is also available. Versions for the Wii Homebrew Channel and Amazon Kindle have also been developed.

OpenSSL is a software library for applications that provide secure communications over computer networks against eavesdropping, and identify the party at the other end. It is widely used by Internet servers, including the majority of HTTPS websites.

gnuplot is a command-line and GUI program that can generate two- and three-dimensional plots of functions, data, and data fits. The program runs on all major computers and operating systems (Linux, Unix, Microsoft Windows, macOS, FreeDOS, and many others). Originally released in 1986, its listed authors are Thomas Williams, Colin Kelley, Russell Lang, Dave Kotz, John Campbell, Gershon Elber, Alexander Woo "and many others." Despite its name, this software is not part of the GNU Project.

boot loader package

software package management system

historical centralized version control system

high-performance dynamic programming language

PuTTY () is a free and open-source terminal emulator, serial console and network file transfer application. It supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. It can also connect to a serial port. The name "PuTTY" has no official meaning.

Rhythmbox is a free and open-source audio player software, tag editor and music organizer for digital audio files on Linux and Unix-like systems.

Mercurial is a distributed revision control tool for software developers. It is supported on Microsoft Windows, Linux, and other Unix-like systems, such as FreeBSD and macOS.

source-level debugger

web browser from GNOME

PyTorch is an open-source deep learning library, originally developed by Meta Platforms and currently developed with support from the Linux Foundation. The successor to Torch, PyTorch provides a high-level API that builds upon optimised, low-level implementations of deep learning algorithms and architectures, such as the Transformer, or SGD. Notably, this API simplifies model training and inference to a few lines of code. PyTorch allows for automatic parallelization of training and, internally, implements CUDA bindings that speed training further by leveraging GPU resources.

OpenVPN is a virtual private network (VPN) 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.

capability-based, real-time operating system (RTOS) being developed by Google

file manager for GNOME

The GNU C Library, commonly known as glibc, is the GNU Project implementation of the C standard library. It provides a wrapper around the system calls of the Linux kernel and other kernels for application use. Despite its name, it now also directly supports C++ (and, indirectly, other programming languages). It was started in the 1980s by the Free Software Foundation (FSF) for the GNU operating system.

dpkg is the software at the base of the package management system in the free operating system Debian and its many derivatives. dpkg is used to install, remove, and provide information about .deb packages.

OpenSSH (also known as OpenBSD Secure Shell) is a suite of secure networking utilities based on the Secure Shell (SSH) protocol, which provides a secure channel over an unsecured network in a client–server architecture.

computer display server protocol

gzip is a file format and a file compression program. The program uses the Deflate algorithm to compress and decompress a single file using the gzip file format.

OpenWrt (from open wireless router) is an open-source project for embedded operating systems based on Linux, primarily used on embedded devices to route network traffic. The main components are Linux, util-linux, musl, and BusyBox. All components have been optimized to be small enough to fit into the limited storage and memory available in home routers.

Gnumeric is a spreadsheet program that is part of the GNOME Free Software Desktop Project. Gnumeric version 1.0 was released on 31 December 2001. Gnumeric is distributed as free software under the GNU General Public License; it is intended to replace proprietary spreadsheet programs like Microsoft Excel. Gnumeric was created and developed by Miguel de Icaza, but he has since moved on to other projects. The maintainer was Jody Goldberg.

cURL (pronounced like "curl", ) is a free and open source CLI app for uploading and downloading individual files. It can download a URL from a web server over HTTP, and supports a variety of other network protocols, URI schemes, multiple versions of HTTP, and proxying. The project consists of a library (libcurl) and command-line tool (curl), which have been widely ported to different computing platforms. It was created by Daniel Stenberg, who is still the lead developer of the project.

Openbox is a free, stacking window manager for the X Window System, licensed under the GNU General Public License. Originally derived from Blackbox 0.65.0 (a C++ project), Openbox has been completely re-written in the C programming language and since version 3.0 is no longer based upon any code from Blackbox. Since at least 2010, it has been considered feature complete, bug free and a completed project. Occasional maintenance is done to keep it working, but only if needed.

small, user-friendly console text editor