Public-domain software

MetaPost refers to both a programming language and the interpreter of the MetaPost programming language.

BDS C (or the BD Software C Compiler) is a compiler for a sizeable subset of the C programming language, that ran on and generated code for the Intel 8080 and Zilog Z80 processors.

CMUCL is a free Common Lisp implementation, originally developed at Carnegie Mellon University.

Snort is a free and open source network intrusion prevention system (NIPS) and network intrusion detection system (NIDS) created by Martin Roesch in 1998.

Low Orbit Ion Cannon (LOIC) is an open source network stress testing and denial-of-service attack application, written in C#.

Mystery House is an adventure game released by On-Line Systems in 1980.

Passage is a 2007 experimental video game developed by Jason Rohrer.

Steel Bank Common Lisp (SBCL) is a free Common Lisp implementation that features ahigh performance native compiler, Unicode support and threading.

qmail is a mail transfer agent (MTA) that runs on Unix.

The djbdns software package is a DNS implementation.

In bioinformatics, BLAST for Basic Local Alignment Search Tool is an algorithm for comparing primary biological sequence information, such as the amino-acid sequences of different proteins or the nucleotides of DNA sequences.

JAMA is a software library for performing numerical linear algebra tasks created at National Institute of Standards and Technology in 1998 similar in functionality to LAPACK.

The Template Numerical Toolkit (or TNT) is a software library for manipulating vectors and matrices in C++ created by the U.

The Cray Operating System (COS) succeeded Chippewa Operating System (shipped with earlier computer systems CDC 6000 series and CDC 7600) and is Cray Research's now discontinued proprietary operating system for its Cray-1 (1976) and Cray X-MP supercomputers, and those platforms' main OS until replaced by UNICOS in the late 1980s.

In computer-based language recognition, ANTLR (pronounced Antler), or Another Tool For Language Recognition, is a parser generator that uses LL(*) for parsing.

Like many Unix commands, SAMtool commands follow a stream model, where data runs through each command as if carried on a conveyor belt.

The MUTE Network (or MUTE-net) is an unmaintained peer-to-peer file sharing network developed with anonymity in mind.

The Invisible Internet Project (I2P) is an overlay network and darknet that allows applications to send messages to each other pseudonymously and securely.

WorldWideWeb (later renamed to Nexus to avoid confusion between the software and the World Wide Web) is the first web browser and editor; it is now discontinued.

Bacula is an open source, enterprise level computer backup system for heterogeneous networks.

MinGW (Minimalist GNU for Windows), formerly mingw32, is a free and open source software development environment for creating Microsoft Windows applications.

ICI is a general purpose interpreted, computer programming language originally developed by Tim Long in the late 1980s.

The Adventures of Quik & Silva is a platform video game originally released in 1991 for the Amiga and Atari ST.

NaCl (pronounced "salt") is an abbreviation for "Networking and Cryptography library", a public domain ".

Hydrus is a suite of Windows-based modeling software that can be used for analysis of water flow, heat and solute transport in variably saturated porous media (e.g., soils).

Epi Info is public domain statistical software for epidemiology developed by Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia (USA).

Epi Map is a module that displays geographic maps with data from Epi Info.

GSSHA (Gridded Surface/Subsurface Hydrologic Analysis) is a two-dimensional, physically based watershed model developed by the Engineer Research and Development Center of the United States Army Corps of Engineers.

Generalized Environmental Modeling System for Surfacewaters or GEMSS is a public domain software application published by ERM.

WorldVistA is an open source implementation of the Veteran Administration's Electronic Health Record system intended for use in health care facilities outside the VA.

World of Arch, (WoA), is a freeware roguelike video game, designed by I.

UBASIC is a freeware (public domain software without source code) BASIC interpreter written by Yuji Kida at Rikkyo University in Japan, specialized for mathematical computing.

Icon is a very high-level programming language featuring goal directed execution and many facilities for managing strings and textual patterns.

High Level Assembly (HLA) is an assembly language developed by Randall Hyde.

Othello (オセロ Osero) is a 1988 video game published by Acclaim Entertainment, made for the Nintendo Entertainment System.

Psychedelia is an early light synthesizer developed by Jeff Minter and published by Llamasoft in 1984.

The High Orbit Ion Cannon, often abbreviated to HOIC, is an open source network stress testing and denial-of-service attack application written in BASIC designed to attack as many as 256 URLs at the same time.

HeadFirst Public Domain was a library of public domain software for the BBC Micro and Acorn Electron 8-bit computers.

Maziacs is an action adventure maze video game published by dk'tronics in 1983 for the ZX Spectrum, Commodore 64 and MSX.

Phyz (Dax Phyz) is a public domain, 2.

Bhuvan, (lit: Earth), is a software application which allows users to explore a 2D/3D representation of the surface of the Earth.

ProTracker is a popular freeware tracker created by Lars Hamre, Anders Hamre, Sven Vahsen and Rune Johnsrud for the Amiga platform.

CSPro, short for the Census and Survey Processing System, is a public domain statistical package developed by the U.

Integrated Software for Imagers and Spectrometers, also abbreviated to Isis, is a specialized software package developed by the USGS to process images and spectra collected by current and past NASA planetary missions sent to Earth's Moon, Mars, Jupiter, Saturn, and other solar system bodies.