All articles starting with O

OpenIGTLink

OpenIGTLink is an open-source network protocol for real-time communication among the computers and devices in image-guided therapy, including surgical navigation software, imaging scanners, and surgical robots.

Opening lead

Opening lead (bridge): the first card played by the defender on declarer's left before dummy is revealed, chosen blind from 13 cards and the auction. Standard leads: top of a sequence, fourth-best from longest suit vs notrump, partner's suit or singleton vs suit contracts; Rule of 11.

Opening Night (song)

"Opening Night" is a 4:19 single by Arctic Monkeys, released 22 January 2026 on War Child Records as lead single for the HELP(2) charity compilation, the band's first new music since The Car (2022), written by Alex Turner and produced by James Ford and Loren Humphrey.

Opening of Incheon port

The opening of Incheon port (제물포 개항) made the fishing village of Jemulpo Korea's third treaty port on 1 January 1883, after Busan and Wonsan.

Opening of Manila to world trade

The opening of Manila to world trade was the Spanish crown's 1834 decision to abolish the Royal Company of the Philippines and open Manila to unrestricted foreign commerce.

Opening of Nagasaki

The opening of Nagasaki (長崎開港) was the establishment of the port of Nagasaki, Japan, for Portuguese trade in 1571 under the Christian daimyo Ōmura Sumitada, beginning its role as Japan's gateway to Europe.

Opening of the Atlantic Ocean

The opening of the Atlantic Ocean began as Pangaea rifted apart about 201 million years ago, with Central Atlantic seafloor spreading starting around 190 Ma.

Sep 23, 2026

Opening of the field boundaries (kai qian mo)

Opening of the field boundaries (开阡陌) was a Qin land reform of the Warring States period, attributed to Lord Shang, in which old field boundaries were redrawn and taxes equalized.

OpenJDK

OpenJDK, the Open Java Development Kit, is the open-source implementation of Java Platform, Standard Edition, open-sourced in 2007 and the upstream for Oracle's JDK and most vendor distributions.

OpenKIM

OpenKIM, the Open Knowledgebase of Interatomic Models, is an open online resource, begun in 2009, that archives, tests, and retrieves interatomic potentials for atomistic materials simulations.

Oct 26, 2026

OpenLineage

OpenLineage is an open standard and API for data lineage collection from running pipelines, using Run, Job, and Dataset events with extensible facets. An LF AI & Data graduated project donated by Datakin, integrated with Airflow, Spark, dbt, Snowflake, and DataHub.

OpenLLaMA

OpenLLaMA is an open source, Apache 2.0 licensed reproduction of Meta AI's LLaMA language model, developed by OpenLM Research and trained on the open RedPajama dataset.

OpenMandriva Lx

OpenMandriva Lx is a free, independent Linux distribution descended from Mandriva Linux, developed by the OpenMandriva Association and notable as the first distribution built with the Clang compiler by default.

OpenMANIPULATOR-X

OpenMANIPULATOR-X is a small open source robotic arm platform from the South Korean robotics company ROBOTIS, with five degrees of freedom, a 380 mm reach, and ROS compatibility for education and research.

OpenMDW license

The OpenMDW license (Open Model, Data, and Weights) is a permissive, weights-first license for AI model distributions, published in 2025 by the Linux Foundation and used by NVIDIA for 19 models.

Oct 26, 2026

OpenMetadata

OpenMetadata is an open-source metadata platform (Apache-2.0 core, Collate commercial edition) unifying data catalog, lineage, quality, governance, and observability, with 130+ connectors, JSON Schema-first design, and an MCP server for AI agents; released 2021, version 2.0 in 2026.

OpenMM

OpenMM is an open-source toolkit for molecular dynamics simulation, usable stand-alone or called from user code, with custom forces, a hardware-independent API, and high performance especially on GPUs.

OpenMMLab

OpenMMLab is an open-source family of PyTorch-based computer vision toolboxes such as MMDetection, launched in 2018 by the Multimedia Lab, a joint SenseTime and Chinese University of Hong Kong laboratory.

OpenMolcas

OpenMolcas is an open-source quantum chemistry software package for ab initio electronic structure calculations, known for multireference methods such as CASSCF and CASPT2, continuing the MOLCAS package since 2018.

OpenMP

OpenMP (Open Multi-Processing) is an API for shared-memory parallel programming in C, C++, and Fortran, built on compiler directives and governed by the OpenMP Architecture Review Board since its first specification in 1997.

OpenMRS

OpenMRS is an open-source electronic health record platform created in 2004 by the Regenstrief Institute and Partners In Health, now serving over 22 million patients in over 80 countries.

OpenMW

OpenMW is a free, open-source game engine that re-implements the engine of The Elder Scrolls III: Morrowind, letting the game run natively on Windows, macOS, and Linux.

Openness to experience

Openness to experience, a Big Five and five-factor personality dimension, covers curiosity, aesthetics, and creativity; measured by BFI (reliability 0.77) and BFI-2 (0.83); predicts creative work, liberal attitudes, and study abroad.

OpenOffice.org

OpenOffice.org, often abbreviated OOo, was an open-source office productivity suite developed by a community project from 2000 to 2011, whose source code came from Sun Microsystems' StarOffice and which created the OpenDocument format.

OpenOrca

OpenOrca is an open-source instruction-tuning dataset for large language models, built by augmenting FLAN Collection prompts with about 1 million GPT-4 and 3.2 million GPT-3.5 responses.

OpenPeak Inc

OpenPeak Inc. was a Boca Raton, Florida technology company that made touch-screen devices and the cloud-hosted ADAM mobile device management platform before a 2016 bankruptcy liquidation.

OpenPGP

OpenPGP is an IETF Proposed Standard, defined in RFC 9580 in July 2024, specifying message formats for public key encryption, digital signatures, compression, and key management.

Openpilot

Openpilot is an open-source driver assistance system developed by comma.ai, released in 2016, that performs adaptive cruise control and lane centering on 335 supported production cars.

OpenPiton

OpenPiton is an open-source, general-purpose manycore processor research platform developed at Princeton University, published at ASPLOS in 2016 and configurable from one core up to 500 million cores.