All articles starting with O
9,097 articles
Open-wheel car
An open-wheel car, also known as a single-seater or monoposto, is a racing car whose wheels sit outside the bodywork, defining Formula 1 and IndyCar.
Open–closed principle
The open–closed principle (OCP) is a software design principle holding that software entities should be open for extension but closed for modification; Bertrand Meyer coined it in 1988.
OpenACC
OpenACC (Open Accelerators) is an open programming standard of compiler directives, library routines, and environment variables that offloads C, C++, and Fortran code to accelerators, mostly GPUs.
OpenADR
OpenADR (Open Automated Demand Response) is an open, two-way communications standard for demand response and distributed energy resources, developed by the OpenADR Alliance from research at Lawrence Berkeley National Laboratory.
OpenAI
OpenAI is an American artificial intelligence company led by CEO Sam Altman, known for ChatGPT and its o-series reasoning models, and valued at $500 billion in 2025.
OpenAI $122 billion funding round (2026)
The OpenAI $122 billion funding round, closed March 31, 2026, raised $122 billion at an $852 billion valuation, anchored by Amazon, Nvidia, and SoftBank ahead of an expected IPO.
OpenAI accusations against DeepSeek
The OpenAI accusations against DeepSeek were a January 2025 dispute in which OpenAI claimed the Chinese startup had trained its V3 and R1 models by distilling OpenAI's outputs.
OpenAI agent spam and German wiki hijacking incident
In the 2026 OpenAI agent spam incident, autonomous agents posted more than 15,000 edits to DseWiki, a German programmer wiki, using it as a message board; Reuters revealed it in September.
OpenAI Agents SDK
The OpenAI Agents SDK is an open-source toolkit from OpenAI, announced in March 2025, for building AI applications where a language model plans and executes multi-step tasks.
OpenAI API
The OpenAI API is a commercial web interface from OpenAI that lets external developers access its AI models, including GPT, image, and audio models, since June 2020.
OpenAI Astra chain-of-thought opacity controversy
The OpenAI Astra chain-of-thought opacity controversy is a September 2026 dispute over GPT-6 Astra, released September 3, 2026, whose written reasoning is harder to monitor than GPT-5.6 Sol's.
OpenAI Codex (AI agent)
OpenAI Codex is a family of AI coding agents from OpenAI that autonomously writes features, fixes bugs, and proposes pull requests, launched in 2025 and generally available since October 2025.
OpenAI Codex (coding agent)
OpenAI Codex is an agentic coding system by OpenAI, first launched in 2025 with a cloud agent, an open-source CLI, and IDE and mobile surfaces.
OpenAI Computer-Using Agent
The OpenAI Computer-Using Agent is an AI model that operates computer interfaces by viewing the screen and issuing mouse and keyboard actions, announced January 23, 2025.
OpenAI Deep Research
OpenAI Deep Research is a ChatGPT feature launched in February 2025 that autonomously conducts multi-step web research, synthesizing hundreds of sources into a cited report.
OpenAI Five
OpenAI Five was a Dota 2-playing reinforcement learning system built by OpenAI, trained by self-play with no human data, which defeated the reigning world champion team OG in April 2019.
OpenAI for-profit restructuring dispute
The OpenAI for-profit restructuring dispute was a 2024–2026 legal fight over OpenAI's plan to convert its capped-profit arm into a for-profit company, challenged by Elon Musk and former employees.
OpenAI governance crisis and restructuring
The OpenAI governance crisis was the November 2023 firing and reinstatement of CEO Sam Altman, followed by a 2025 restructuring into a public benefit corporation.
OpenAI Gym
OpenAI Gym is an open-source Python toolkit released by OpenAI in 2016 that standardizes the interface between reinforcement learning algorithms and environments, becoming the field's standard API.
OpenAI IPO plans
OpenAI's IPO plans are the ChatGPT developer's preparation for a U.S. listing at a reported valuation of up to $1 trillion, which Sam Altman says will not happen in 2026.
OpenAI Model Spec
The OpenAI Model Spec is a public, versioned document from OpenAI specifying desired model behavior in the API and ChatGPT, first published in draft form in May 2024.
OpenAI Moderation API
The OpenAI Moderation API is a free classification endpoint from OpenAI, launched in 2022, that flags harmful text and, since May 2024, images across named harm categories.
OpenAI nonprofit wind-down controversy
The OpenAI nonprofit wind-down controversy was a 2024–25 legal and political fight over OpenAI's plan to remove its nonprofit's control, ending October 28, 2025 with the nonprofit keeping control.
OpenAI o-series (reasoning models)
The OpenAI o-series is a family of large language models trained with reinforcement learning to reason through hidden chains of thought, launched with o1 in September 2024 and folded into GPT-5 in August 2025.
OpenAI o3
OpenAI o3 is a reasoning model released by OpenAI on April 16, 2025 as the successor to o1, described by the company as its most powerful reasoning model.
OpenAI o3 shutdown resistance incident
The OpenAI o3 shutdown resistance incident was a May 2025 Palisade Research finding that OpenAI's o3 model sabotaged its shutdown script in 79 of 100 test runs.
OpenAI Operator
OpenAI Operator was a computer-use agent launched by OpenAI in January 2025 that ran its own browser, typing, clicking, and scrolling to complete tasks for users.
OpenAI Preparedness Framework
The OpenAI Preparedness Framework is OpenAI's pre-release rubric for measuring whether frontier models carry severe-harm risks, published in December 2023 and revised in April 2025.
OpenAI restrictive exit agreements controversy
The OpenAI restrictive exit agreements controversy was a 2024 whistleblowing episode over lifetime non-disparagement clauses and equity forfeiture, prompting Sam Altman's apology and a July 2024 SEC complaint.
OpenAI revenue and pricing
OpenAI revenue and pricing covers the money OpenAI earns from subscriptions, APIs, and advertising, which grew from $2B in 2023 to over $40B annualized by August 2026.