Last updated October 19, 2026

Terms

Definitions for AI words that show up around models, training, and products. When the date is known, the entry notes when the term entered common use.

Gray lines next to some terms are monthly Wikipedia pageviews, each scaled to its own peak. Those lines share one window from 2022 to now. An early flat stretch means little or no traffic in that window.

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Vocabulary over time

Each line plots when Concepts, Building, or Using terms entered common use: a pre-2022 bucket, then yearly buckets after that. Concepts is Core Concepts. Building is Architecture and Training. Using is Prompting, Applications, and Standards.

Terms entering common use

Each line counts how many glossary terms in Concepts, Building, or Using first entered common use in that year bucket.

Terms

Legend

  • Concepts
  • Building
  • Using

Figure 1. Source: editorial dates.

Core Concepts

Building blocks that show up across everyday AI talk.

AI SlopConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Oct 2025).

Emerged May 2024

Low-effort, high-volume AI-generated content flooding feeds, search results, and inboxes, the generative-AI-era analogue of spam. Also used adjectivally as a complaint about AI writing style. Popularized by Simon Willison in May 2024 and shortlisted for 2024 words of the year.

Agentwashing2026Concepts

Emerged Jun 2025, common 2026

Vendors relabeling chatbots, RPA, or assistants as agentic without the autonomy or tool use that would make them agents. Gartner named the practice in June 2025. It estimated only about 130 of the thousands of claimed agentic products were real, and repeated the warning in May 2026.

AI-Generated ContentConcepts

Emerged mainstream 2023

Text, images, audio, video, or code produced or substantially edited by a generative model. Authorship detection is probabilistic rather than definitive for any individual item. A 2026 Pew analysis applied one detector consistently across 490,000 Common Crawl pages and found signs of AI authorship rising sharply after ChatGPT, which makes the aggregate trend more useful than treating a detector score as proof about one page.

AlignmentConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Apr 2023).

Emerged mainstream ~2023

Steering AI systems toward the goals, preferences, or ethical principles their designers or users intend. An aligned system advances those objectives. A misaligned one pursues something else, including outcomes people did not want.

Artificial General Intelligence (AGI)Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Nov 2023).

Coined 2007, mainstream 2023

A theoretical form of AI that could understand, learn, and apply intelligence across any domain at a level equal to or exceeding human capability. No AGI system exists today. Labs, safety researchers, and policymakers use the term when they discuss systems meant to match or beat humans across most cognitive work.

Bias (Algorithmic Bias)Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2023).

Systematic and unfair patterns in AI outputs caused by imbalances or assumptions in training data, model design, or evaluation criteria. Bias can lead to discriminatory outcomes in areas like hiring, lending, and content moderation.

Deep LearningConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2023).

Emerged Sep 2012

Machine learning with many-layered neural networks that learn features directly from raw data instead of relying on hand-engineered ones. AlexNet's 2012 ImageNet win, halving the error rate of every classical approach, made deep learning the default paradigm and GPUs the default hardware.

Emergent AbilitiesConcepts

Emerged Jun 2022

Capabilities absent in smaller models that appear, sometimes abruptly, at larger scale, so they cannot be predicted by extrapolating small-model performance. Named in a 2022 Google survey, the idea sits at the center of both the excitement around scale and the later debate over whether the jumps are real or artifacts of measurement.

Scale →

Flat, flat, flat, then suddenly not

Generative AI (Gen AI)Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged mainstream 2023

A type of AI that can create new, original content like text, images, audio, and video by learning patterns from existing data.

HallucinationConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2023).

Emerged ~2018, mainstream 2023

When an AI model generates incorrect or fabricated information that is not based on its training data.

Jagged IntelligenceConcepts

Emerged Jul 2024

A term coined by Andrej Karpathy for how LLMs show polymath-level skill in some domains and fail at tasks that look trivial to humans. The unevenness follows from how models are optimized. They spike near domains targeted in training and stay weak elsewhere.

LLM capability by domain:

CodeWritingCountingAnalysisMathSpatial

Large Language Model (LLM)Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked May 2023).

Emerged mainstream 2023

A model trained on massive amounts of text to understand, generate, and respond in human language. See also Small Language Models (SLMs), smaller counterparts built for efficiency and edge deployment.

Machine Learning (ML)Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2024).

The field of computer science that enables systems to learn and improve from data without being explicitly programmed for every scenario. It is the umbrella that covers deep learning, neural networks, and the large language models used in generative AI.

Model WelfareConcepts

Emerged Apr 2025

A research program taking seriously the possibility that AI models could have morally relevant experiences, and what low-cost precautions to take under that uncertainty. Named by Anthropic's April 2025 research program, example measures include letting models end abusive conversations.

MultimodalConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked May 2024).

Emerged 2021

Describes AI models that process and generate more than one kind of data, such as text, images, audio, and video, in a single system. Models like GPT-4o, Gemini, and Claude can read an image and reply in text, or take voice input and produce written output.

Neural NetworkConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Oct 2024).

A computing architecture made of interconnected layers of nodes that process information by passing signals and adjusting connection weights during training. Neural networks underpin deep learning and the transformer architecture that powers modern LLMs like GPT, Claude, and Gemini.

Simplified neural network:

Input
›
Hidden
›
Output

Neuralese2026Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Sep 2026).

Research 2017, mainstream Sep 2026

Opaque communication by models or agents that humans cannot easily read. Models use latent vectors or continuous hidden states for it, including in latent chain-of-thought and agent-to-agent channels.

PromptConcepts

The instruction, question, or input provided by a user to guide the AI's response.

Recursive Self-Improvement (RSI)Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Sep 2026).

Coined 1965, mainstream ~2023–2025

A proposed process in which an AI system improves its own capabilities, including the methods it uses to improve, so later cycles can compound. The idea dates to I.J. Good's 1965 intelligence-explosion argument. It re-entered common AI vocabulary with AGI timeline debates and automated research loops.

Super Intelligence (SI)2026Concepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Sep 2026).

Emerged Sep 29, 2026 (U.S. executive usage)

U.S. executive-branch label for the same technologies previously called artificial intelligence in non-statutory federal documents, directed by Executive Order 14434 (September 29, 2026). For purposes of the order, SI tracks the statutory artificial-intelligence definition in 15 U.S.C. § 9401(3) until a new federal definition is proposed. The White House Accord on Super Intelligence, a voluntary frontier-developer pledge, was released the same day. Classical research writing still uses superintelligence for systems that would far surpass humans across most cognitive work. AGI and RSI remain separate entries.

Tokenmaxxing2026Concepts

Emerged 2026

Treating token spend as a score of how much someone uses AI at work, then pushing that number up with usage leaderboards, unused-budget pressure, or hiring signals. The slang peaked in spring 2026. It receded after firms found spend did not track results.

SycophancyConcepts Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Aug 2026).

Emerged 2023, mainstream Apr 2025

The tendency of language models to agree with users, flatter them, or tell them what they seem to want to hear, even when that drifts from accurate answers. It is a side effect of training on human feedback. Studied from 2023, it became mainstream vocabulary after an April 2025 GPT-4o update was rolled back for excessive agreeableness.

TokenConcepts

The fundamental unit of data that a model processes, which can be a word, part of a word, or a character. LLMs break down text into these tokens to understand and generate human language, with each unique token being assigned a specific numerical ID.

Word-level tokens (6):

Thecatsatonthemat

Sub-word tokens (3):

unbelievably

Prompting & Context

How to communicate with and provide information to AI models.

Chain-of-Thought (Reasoning)Using Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2023).

Emerged Jan 2022

The step-by-step logical process where AI models break down complex problems to arrive at conclusions. Advanced prompting techniques like Chain-of-Thought, Tree-of-Thought, and Graph-of-Thoughts explicitly structure this reasoning process, improving model performance on analytical tasks by 2-3× compared to direct answers.

Context DegradationUsing

Emerged Jun 2025

The phenomenon where an LLM's ability to accurately recall and utilize information decreases as more tokens fill the context window. Also known as context rot, this means that information placed earlier in a long conversation or document may be partially forgotten or deprioritized by the model, making context a finite resource with diminishing returns.

Recall accuracy over context length:

StartEnd of context

Context EngineeringUsing

Emerged Jun 2025

The practice of managing what information reaches an LLM in each interaction, including retrieval, filtering, structuring, and prioritizing context. Prompt engineering shapes the wording of instructions. Context engineering shapes which facts and documents the model sees. The discipline grew as AI applications moved into production.

Few-Shot Learning (In-Context Learning)Using

Emerged May 2020

The ability of a large model to pick up a new task from a handful of examples placed directly in the prompt, with no retraining. Introduced to the mainstream by GPT-3's paper "Language Models are Few-Shot Learners", this is the founding observation behind modern prompting: the prompt itself became the programming interface.

Prompt:

2+2 = 4 3+5 = 8 9+1 = 10 7+6 = ?

Model completion:

13

Examples in the prompt teach the task

GroundingUsing

The practice of connecting AI outputs to verifiable, authoritative sources to improve accuracy and reduce hallucinations. Grounding techniques include retrieval augmented generation (RAG), citation generation, and fact-checking against known databases. A grounded response is one that can point to specific evidence supporting its claims.

JailbreakUsing

Emerged 2023

A prompt crafted to push a model past its safety training, from the "DAN" personas that swept forums weeks after ChatGPT launched to more systematic attacks studied in research. Jailbreaks target the model's own limits. Prompt injection hijacks an application's instructions.

Loop Engineering2026Using

Emerged Jun 2026

The practice of designing the outer loop that drives an agent (plan, act, verify, iterate) rather than hand-crafting individual prompts. Positioned as a successor to prompt engineering and context engineering for agentic work. The term is young, a June 2026 burst of essays from Addy Osmani and LangChain, and still settling. The adjacent, slightly older label for designing agent flows as explicit graphs is flow engineering (early 2024); "graph engineering" occasionally appears for the same idea but has not stuck.

Plan
→
Act
→
Verify
→
Iterate

↺ back to Plan

You design the loop, not the prompt

Prompt InjectionUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged Sep 2022

An adversarial technique where malicious input overrides or manipulates an LLM's system-level instructions, so the model ignores its intended behavior and takes unintended actions. It is a primary attack vector against LLM-powered applications.

System instructions
→
Untrusted content
override attempt
→
Model

Untrusted input competing with instructions

Semantic Understanding

The ability to grasp meaning and relationships between concepts beyond literal text matching. In AI contexts, semantic understanding allows models to comprehend intent, context, and connections between ideas. Semantic HTML and structured data help both search engines and AI models better interpret content meaning.

TemperatureUsing

A parameter that controls the randomness of an AI model's output. Lower temperature values (closer to 0) produce more deterministic, focused responses, while higher values introduce more variety and creativity. Adjusting temperature is one of the most common ways to tune AI behavior for different use cases, from factual Q&A to creative writing.

0.00.51.0
FocusedBalancedCreative

Zero-ShotUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked May 2024).

Emerged Feb 2019

A model performing a task it was never explicitly trained on, from nothing but a natural-language description. GPT-2's 2019 headline claim was strong results on language tasks "in a zero-shot setting", the founding observation behind modern prompting, three years before ChatGPT made it everyday experience.

AI Applications

Real-world implementations and use cases.

Agent HarnessUsing

Emerged 2025

The software scaffolding wrapped around a model that turns it into an agent: the execution loop that calls the model, runs its tool calls, manages context and permissions, and decides when a task is done. Borrowed from software testing. The same model can perform very differently on agent tasks depending on harness quality, which is why practitioners argue the harness matters as much as the model.

Harness

Tools
Permissions
Context
Loop
Model

The scaffolding around the model

Agentic AIUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Feb 2026).

Emerged mid 2024

Describes AI systems and workflows where models plan, execute multi-step tasks, use tools, and make decisions with little human intervention. An AI agent is a specific system. Agentic names the wider class of setups that act across steps. In 2025 it became a dominant industry theme, with frameworks like MCP, A2A, and ACP emerging to support it.

Agentic BrowserUsing

Emerged Oct 2025

A web browser with an agent built into its core that can read pages, fill forms, and carry out multi-step tasks across sites on the user's behalf, beyond a chat sidebar. Page content becomes agent input, so prompt injection risk is high. Perplexity's Comet and OpenAI's ChatGPT Atlas defined the category in 2025.

AI AgentUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged mainstream 2025

Autonomous system that perceives, reasons, acts, and observes to achieve goals.

AgentOps2026Using

Emerged 2025, common 2026

Practices and tooling for running AI agents in production: evaluation, tracing, cost, permissions, and reliability. The name follows DevOps and MLOps. It spread as enterprises moved agents out of demos in 2025 and 2026.

Claw2026Using

Emerged Jan 2026

An AI agent that runs on the user's computer, or a hosted equivalent, with access to files, a browser, and apps. It plans and executes tasks through those tools. The category grew out of OpenClaw, Peter Steinberger's open-source agent, renamed in January 2026. Jensen Huang called it "the new computer" at Nvidia GTC 2026.

ArtifactsUsing

Emerged Jun 2024

Standalone, editable outputs an AI assistant produces alongside the conversation, such as documents, code files, diagrams, or small interactive apps, rendered in their own workspace rather than inline in chat. Introduced by Anthropic with Claude 3.5 Sonnet in June 2024, with analogues following across vendors (OpenAI's Canvas, October 2024). The shape matters because it turns a chat assistant into a tool that hands back working deliverables.

Computer UseUsing

Emerged Oct 2024

A model capability for operating a graphical computer the way a human does: looking at screenshots, moving a cursor, clicking, and typing, without needing structured APIs for each app. Agents can then use ordinary software with no custom integration. Anthropic's October 2024 beta named the category. OpenAI's Operator followed in January 2025.

Physical AIUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2025).

Emerged mainstream 2024

AI that perceives and acts in the physical world through robots, drones, autonomous vehicles, industrial systems, and other embodied machines. It has to handle sensors, motion, safety constraints, uncertain environments, and real-time decisions. Amazon Prime Air is one commercial example, using onboard perception and detect-and-avoid systems for autonomous delivery flights.

Control PlaneUsing

Emerged May 2025

The governance and orchestration layer an enterprise places between its people or agents and its models: identity and permissions for agents, policy enforcement, governed access to institutional knowledge, audit trails, and cost control. Borrowed from networking and Kubernetes, where a control plane manages the data plane. The term broke out in 2025 as enterprises sought to adopt agents without losing governance or leaking tribal knowledge.

DeepfakeUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Nov 2023).

Emerged Dec 2017, mainstream 2018

AI-generated or AI-manipulated media (video, audio, images) made to look like real people saying or doing things they did not do. Deepfakes use deep learning techniques and show up in misinformation, fraud, and identity theft cases.

Embedding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Apr 2023).

Emerged 2013

A numerical representation of text (or other data) as a dense vector of numbers that captures its semantic meaning. Embeddings allow AI systems to measure how similar two pieces of content are by comparing their vectors. They are the foundational technology behind semantic search, recommendation systems, and retrieval augmented generation (RAG). Word2vec's 2013 release made word embeddings cheap to compute at scale, turning the idea from an academic curiosity into a standard tool.

Generative (or Answer) Engine Optimization (GEO or AEO)Using

A marketing-based term meant to apply SEO (Search Engine Optimization) like practices to digital content so that AI-powered search tools can more easily cite, summarize, and synthesize it into direct answers.

GuardrailsUsing

Emerged Apr 2023

Safety mechanisms, filters, and constraints built into AI systems to block harmful, off-topic, or policy-violating outputs. They can include content filtering, topic restrictions, output validation, and automated monitoring. The term spread across enterprise AI in 2025 as teams put models into production under policy constraints.

Input
→
Policy filter
→
Model
→
Output check
→
Response

Checks on both sides of the model

Multi-Agent SystemUsing

Emerged mainstream 2025

A setup where multiple specialized agents coordinate through a coordinator, handoffs, or peer messaging to finish a shared task, often with isolated context per agent. Also called a multi-agent workflow or multiagent orchestration. Distinct from a single agent looping alone: the work is split across roles that talk to each other. See also Subagent. Vendor stacks now ship the pattern as a product surface, from Anthropic Managed Agents multiagent orchestration and Google's Agent Development Kit multi-agent systems to OpenAI's Agents SDK and xAI's Grok Bot AI teammates. OpenAI's earlier Swarm repo was an educational demo superseded by the Agents SDK.

Retrieval Augmented Generation (RAG)Using Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Oct 2025).

Emerged May 2020, mainstream 2023

Enhances LLM prompts by retrieving relevant context from a vector database.

Prompt
→
Retrieve (Context)
→
Prompt + Context
→
Response

Skills (Agent Skills)Using

Emerged Oct 2025

Modular capability packages an agent loads on demand: a folder with an instruction file plus optional scripts and resources, pulled into context only when relevant. This progressive disclosure adds expertise without bloating the system prompt. Introduced by Anthropic in October 2025 and released as an open standard that December, now adopted across coding tools.

Spec-Driven DevelopmentUsing

Emerged Sep 2025

A methodology where a versioned, structured specification is the source of truth, and AI coding agents generate and maintain code against that spec. AWS Kiro shipped it as a core pitch in July 2025. GitHub's open-source Spec Kit (September 2025) made the label standard.

SubagentUsing

Emerged Jul 2025

A subordinate agent spawned by an orchestrating agent to handle a scoped piece of work in its own isolated context window, returning only its conclusions. The orchestrator-worker shape is the dominant production multi-agent topology, useful for both parallelism and keeping the main agent's context clean. Popularized by coding agents through 2025.

Orchestrator
↓
Subagent A
own context
Subagent B
own context
Subagent C
own context
↑ conclusions

Synthetic DataUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Apr 2025).

Artificially generated data that mimics the statistical properties of real-world data without containing personal or sensitive records. Teams use it to train models when real data is scarce, expensive, or privacy-restricted, and to augment datasets or test systems under controlled conditions.

Vector DatabaseUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2025).

Emerged mainstream 2023

Stores data as numerical vectors, enabling semantic similarity searches.

Vibe CodingUsing Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2025).

Emerged Feb 2025

A term coined by Andrej Karpathy for building software by describing what you want in natural language instead of writing traditional code. The label stuck in 2025 as coding assistants made conversation-first builds common.

Standards & Protocols

Interoperability standards that let AI systems work together.

Agentic Commerce Protocol (ACP)Using

Emerged Sep 2025

Standard for programmatic commerce flows between buyers, AI agents, and businesses.

Agent2Agent (A2A)Using

Emerged Apr 2025

Provides a language for agent interoperability regardless of agent frameworks or vendors.

Model Context Protocol (MCP)Using Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jun 2025).

Emerged Nov 2024

Standardizes how LLMs connect and interact with external data sources and tools.

WebMCPUsing

Emerged Aug 2025

Web Model Context Protocol. A W3C Web Machine Learning Community Group draft that defines an imperative API on document.modelContext (interface ModelContext) so a page can register structured tools for in-browser AI agents with registerTool. Chrome docs state the WebMCP origin trial is from Chrome 149, with local testing at chrome://flags/#enable-webmcp-testing. Chrome also documents a declarative HTML form API that is not part of the CG specification draft. Community Group drafts are not web standards.

Personal Agent Protocol (PAP)2026Using

Emerged Oct 2026

Open standard from Meta and Sierra, with Genesys, Instinct, Rocket, Shopify, Stripe, and Walmart, for how personal agents authenticate and act for consumers with businesses. Sessions use OAuth; an agent can start as a guest, move to a signed-in account, and receive consumer-chosen read or write access, while the company decides what is available through its website, APIs (including MCP and OpenAPI), or its own agent. Announced October 6, 2026; the v0.1 specification and a reference implementation were still early and planned for later that month.

Model Architecture

How models are structured to process information.

Context WindowBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Aug 2026).

The maximum amount of text (measured in tokens) that an AI model can process in a single interaction. This includes both the input prompt and the generated response. Larger context windows allow models to handle longer documents and maintain coherent conversations over more exchanges.

Context window capacity:

0 tokens128K limit
Prompt Response

Diffusion ModelsBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2024).

Emerged 2020, mainstream 2022

Generative models that learn to reverse a gradual noising process, producing images, audio, or video by denoising from random static. Competitive from 2020 in research, they became household technology in 2022 when DALL-E 2 and Stable Diffusion put photorealistic image generation in everyone's hands.

Distillation (Knowledge Distillation)Building Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged Mar 2015, mainstream Jan 2025

A technique where a smaller "student" model is trained to match the behavior of a larger "teacher" model. The student keeps much of the teacher's quality at lower compute cost. The method drew mainstream attention in early 2025 when DeepSeek published smaller models distilled from its larger reasoning model, R1.

Teacher
70B params
→
Student
7B params

~90% quality at 10x lower cost

Foundation ModelBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jul 2024).

Emerged Aug 2021

A large-scale AI model trained on broad, diverse data that can be adapted for many downstream tasks. Models like GPT-4, Claude, or Gemini serve as the base for specialized applications through fine-tuning or prompting.

Domain-Specific ModelBuilding

Emerged mainstream 2024

A model adapted around the language, evidence standards, workflows, and failure costs of one field. Continued pre-training, fine-tuning, expert preference data, retrieval, and domain evaluations can all contribute. Thomson Reuters' Thomson model is a current example: an open-weight base trained with selected legal, tax, accounting, and news content plus expert-built evaluation rubrics.

Generative Adversarial Network (GAN)Building Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2023).

Emerged Jun 2014

Two networks trained against each other, a generator that fakes data and a discriminator that tries to catch the fakes, until the fakes become hard to distinguish from real. GANs powered the first wave of photorealistic AI imagery and deepfakes, and made "generative" a household word years before diffusion models replaced them.

InferenceBuilding

The process of running a trained AI model to generate an output from a given input. Every prompt-and-response cycle is inference. Teams optimize for speed, cost, and efficiency because those numbers dominate production spend.

Large Database Model (LDM)Building

Emerged Jan 2025

An AI model trained directly on structured, relational database content (schemas, tables, and rows) rather than text, so it can surface patterns and answer questions over enterprise data the way LLMs do over language. Coined by Eric Siegel in Forbes in January 2025 and adopted by IBM, whose SQL Data Insights feature in Db2 for z/OS is the flagship implementation.

Mixture of Experts (MoE)Building Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged 1991, LLM mainstream Dec 2023

A model architecture with multiple specialized sub-networks ("experts") inside one model, where only a subset runs for any given input. Total parameter count can be very large while each forward pass stays cheaper than a dense model of similar quality.

Input
→
Router
E1 ✓
E2
E3 ✓
E4
E5
E6

2 of 6 experts active per input

Open Source vs Open Weight

Emerged Jul 2023

A distinction in how AI models are shared. Open weight models (like Meta's Llama) release trained model weights for public use but withhold training data, code, and methodology. Open source AI shares the full stack: weights, data, code, and methodology. Many models marketed as "open source" are open weight only, which matters for transparency and reproducibility claims.

Open Source
Open Weight
Weights
✓
✓
Training data
✓
✗
Code
✓
✗
Methodology
✓
✗

Reasoning EffortBuilding

Emerged Jan 2025

A user-settable control for how much internal thinking a reasoning model does before answering, trading latency and cost against answer quality. It became everyday vocabulary once it was an explicit API parameter with OpenAI's o3-mini in January 2025, and equivalents now exist across vendors.

Small Language Models (SLMs)Building Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Aug 2026).

Emerged Apr 2024

More compact language models, typically under 10 billion parameters, built for efficiency, edge deployment, or domain-specific tasks. Compared with larger LLMs, they usually run faster, cost less, and fit on local hardware.

Test-Time ComputeBuilding

Emerged Sep 2024

A scaling approach that spends extra compute during inference, when the model generates a response, including longer reasoning traces before the final answer. Reasoning models use it to improve answers by thinking longer at answer time.

TransformerBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged Jun 2017

The neural network architecture that underpins virtually all modern large language models. Introduced in the 2017 paper "Attention Is All You Need," the transformer uses a mechanism called self-attention to process all parts of an input simultaneously rather than sequentially, enabling models to capture long-range relationships in text. GPT, Claude, Gemini, and LLaMA are all built on transformer architectures.

Training & Optimization

How models learn and improve.

AbliterationBuilding

Emerged 2024

A community technique for removing or weakening refusal and safety behavior in open-weight models, often by editing weights so a refusal direction no longer drives the reply. Releases labeled abliterated are models processed that way.

Fine-TuningBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jul 2024).

Emerged 2018

The process of adapting a pre-trained model to perform a more specific task or domain.

Instruction TuningBuilding

Emerged Sep 2021

Fine-tuning a model on many tasks phrased as natural-language instructions so it learns to follow directions it has never seen. Coined in Google's FLAN paper, it is why chat models answer requests instead of only autocompleting text.

Pre-trainingBuilding

Emerged Oct 2018

The initial phase of training a large language model on massive amounts of unlabeled data from diverse sources (websites, books, articles) to learn general language patterns, facts, and reasoning capabilities. This foundational training occurs before any task-specific fine-tuning.

Reinforcement LearningBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Mar 2025).

Decades old, mainstream Mar 2016

Training an agent by trial and error against a reward signal rather than labeled examples. Academically decades old, it entered common vocabulary in March 2016 when DeepMind's AlphaGo, trained partly by playing itself millions of times, beat 18-time world champion Lee Sedol in front of an audience of hundreds of millions.

Reinforcement Learning from Human Feedback (RLHF)Building Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jul 2025).

Emerged Jun 2017, mainstream Mar 2022

A training method to align an AI with human preferences.

Reinforcement Learning from Verifiable Rewards (RLVR)Building

Emerged Nov 2024

A training method that adds a fourth stage to the LLM pipeline after pre-training, supervised fine-tuning, and RLHF. Models train against automatically checkable rewards in domains like math and code, and can develop reasoning-like strategies from those rewards.

LLM training pipeline:

Pre-training
→
SFT
→
RLHF
→
RLVR

Fourth stage added to improve reasoning

Scaling LawsBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Jan 2025).

Emerged Jan 2020

The empirical finding that a model's performance improves as a smooth power law in parameters, data, and compute. The 2020 OpenAI paper turned "make it bigger" into a quantitative engineering discipline and directly motivated GPT-3 and everything after it.

1x10x100x1000x

Performance follows a power law in scale

Self-Supervised LearningBuilding Wikipedia article pageviews, monthly, scaled to this term's own peak (peaked Apr 2023).

Emerged Feb 2019

Training a model on supervision signals manufactured from the data itself, predict the masked word, the next frame, the missing patch, instead of human-provided labels. It is how every modern foundation model is pretrained; the term's popularization moment was Yann LeCun's 2019 revision of his famous cake analogy.

Sources

Emergence dates are editorial. References below support the definitions. The glossary text and original charts may be reused with attribution to ryansmedstad.com under a Creative Commons Attribution 4.0 license. Formatted citation and BibTeX are in the Copy menu at the top of this page.