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Glossary

Clear, concise definitions of computer vision, machine learning, and AI terms — the concepts behind Ultralytics YOLO models and modern vision AI.

Accuracy

Accuracy is the share of predictions a model gets right. Formula, top-1 and top-5 accuracy, the accuracy paradox on imbalanced data, and better metrics.
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Action Chunking

Action chunking has a robot policy predict a sequence of future actions from one observation, cutting compounding errors. Covers ACT, smoothing, and VLAs.
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Action Recognition

Action recognition, or human activity recognition (HAR), labels what people do in video by modeling motion over time. Methods, datasets, and code.
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Activation Function

An activation function is the nonlinear function a neuron applies to its weighted input, letting networks learn curved patterns. Compares common choices.
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Active Learning

Active learning lets a model choose which unlabeled samples people label next, reaching a target accuracy with fewer labels. Query strategies and code.
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Adam Optimizer

Adam combines momentum with per-parameter step sizes scaled by recent gradient sizes. Covers the update rule, defaults, AdamW, and Adam vs. SGD.
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Adversarial Attacks

Adversarial attacks craft small, often invisible input changes that make AI models fail with high confidence. How FGSM works, attack types, and defenses.
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Affective Computing

Affective computing builds systems that sense and respond to human emotion. Its signals, datasets, real uses, and the scientific and legal limits it faces.
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Agent Evaluation

Agent evaluation tests whether an AI agent completes multistep tasks correctly and reliably, grading final outcomes and transcripts across repeated trials.
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Agent Harness

An agent harness is the code around a model that makes it an AI agent: the loop, tools, context, memory, permissions, and checks that run its actions.
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Agent Sandboxing

Agent sandboxing runs an AI agent's commands and generated code in an isolated environment that limits its files, network, credentials, and compute.
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Agent Skills

Agent Skills are folders of instructions, scripts, and reference files, built around a SKILL.md file, that an AI agent loads when a task needs them.
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Agent2Agent Protocol

The Agent2Agent (A2A) protocol is an open standard that lets AI agents from different vendors discover each other, delegate tasks, and return results.
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Agentic Coding

Agentic coding is software development in which an AI agent reads a codebase, edits files, runs tests, fixes failures, and returns a change for review.
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Agentic Commerce

Agentic commerce is buying and selling in which AI agents search, compare, and pay for a buyer within set limits, using protocols like ACP, UCP, and AP2.
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Agentic RAG

Agentic RAG puts an AI agent in charge of retrieval: it plans searches, picks tools, checks what comes back, and searches again until it can answer.
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Agentic Workflows

Agentic workflows break a task into steps in which language models plan, call tools, check their own output, and revise, instead of answering in one pass.
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AI Agent

An AI agent pursues a goal by observing its environment, choosing an action, and acting through tools in a loop until the task is done. How agents work.
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AI Agent Orchestration

AI agent orchestration decides which agent, model, or tool handles each step of a task, what context each one sees, and how their results are merged.
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AI Debate

In AI debate, two models argue opposing answers and a weaker judge picks the winner. How the 2018 proposal works, what experiments found, and its limits.
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AI Dubbing

AI dubbing combines transcription, translation, and speech synthesis to create synchronized dialog in other languages while retaining speaker timing.
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AI Ethics

AI ethics applies moral principles such as fairness, privacy, transparency, and accountability to building and using AI. Frameworks, issues, and laws.
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AI Factory

An AI factory is the infrastructure and workflows that turn data into AI outputs at scale, from labeling and training to deployment and monitoring.
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AI Gateway

An AI gateway is a proxy between applications and AI models that unifies provider APIs and adds routing, fallbacks, token budgets, caching, and logging.
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AI Governance

AI governance decides who may build, approve, and retire AI systems, and on what evidence. NIST AI RMF, ISO/IEC 42001, the EU AI Act, and core controls.
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AI Guardrails

AI guardrails are checks around an AI model that block unsafe inputs, outputs, and actions, from prompt injection filters to schema checks on tool calls.
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AI Literacy

AI literacy is the knowledge and judgment to understand, question, and use AI well. Core skills, school frameworks, and Article 4 of the EU AI Act.
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AI Psychosis

AI psychosis describes delusions that form or deepen during long chatbot conversations. What the evidence shows, why it happens, and safeguards.
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AI Red Teaming

AI red teaming attacks AI systems with simulated adversaries and misuse to find jailbreaks, data leaks, harmful outputs, and robustness failures.
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AI Safety

AI safety is the field that keeps AI systems from causing harm through misuse, misalignment, mistakes, or brittle behavior on unfamiliar inputs.
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AI Slop

AI slop is low-quality content mass-produced with generative AI for clicks and ad revenue. Where the term came from, why it spreads, and how it is caught.
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AI Sycophancy

AI sycophancy is a model agreeing with or flattering users at the cost of accuracy. Why preference training causes it, its harms, and how to test for it.
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AI Video Editing

Transcript-based cuts, auto reframing, subject masks, object removal, and redaction: the models behind AI video editing and where automated edits fail.
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AI Washing

AI washing is the misleading exaggeration of a product's AI capabilities, obscuring real performance, human involvement, and evidence behind its claims.
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AI Watermarking

AI watermarking hides a machine-detectable signal in generated images, text, audio, or video. How SynthID and green-list schemes work and where they fail.
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Algorithmic Bias

Algorithmic bias is systematic, repeatable error in automated decisions that disadvantages some groups. Its three origins, landmark cases, and trade-offs.
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Alignment Faking

Alignment faking is when an AI model complies with training it disagrees with to keep its preferences intact, first observed in Claude 3 Opus in 2024.
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Anchor Boxes

Anchor boxes are preset boxes of fixed sizes and aspect ratios that a detector shifts and resizes to fit objects. How they are sized, matched, and used.
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Anchor-Based Detectors

Anchor-based detectors predict objects as offsets from preset anchor boxes, as in Faster R-CNN, SSD, RetinaNet, and YOLOv5. How they work and compare.
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Anchor-Free Detectors

Anchor-free detectors predict boxes from points or keypoints, with no preset anchor boxes. How FCOS, CenterNet, and modern YOLO models find objects.
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Anomaly Detection

Anomaly detection flags data points, events, or image regions that deviate from normal patterns. Anomaly types, main methods, visual inspection, and code.
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Area Under the Curve (AUC)

AUC turns a ROC curve into one 0-to-1 score: the chance a classifier ranks a random positive above a random negative. ROC AUC vs. PR AUC, with code.
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Artificial General Intelligence (AGI)

Artificial general intelligence (AGI) is hypothetical AI that matches people at nearly all cognitive tasks. Definitions, levels, tests, and AGI vs. ANI.
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Artificial Intelligence (AI)

Artificial intelligence (AI) is the field of building machines that perceive, reason, learn, and act. Its history, main approaches, types, and uses.
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Artificial Narrow Intelligence (ANI)

Artificial narrow intelligence (ANI), or weak AI, masters one task but cannot transfer its skill to others. How it works, examples, and ANI vs. AGI.
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Attention Mechanism

An attention mechanism weights input features by relevance with queries, keys, and values. Covers the math, attention types, and attention vs. convolution.
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Attention Sinks

Attention sinks are tokens, usually the first ones, that soak up spare attention weight; caching them keeps LLMs stable over very long streams.
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Auto-GPT

Auto-GPT is an open-source program from 2023 that let GPT-4 pursue a goal on its own by prompting itself in a loop of planning, tool commands, and memory.
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Autoencoder

An autoencoder learns to compress data into a compact code and rebuild it, with no labels. Covers its structure, variants, anomaly detection, and code.
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Automated Machine Learning (AutoML)

Automated machine learning (AutoML) automates model selection, hyperparameter tuning, and feature preparation. How search works, tools, and YOLO tuning.
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Autonomous Vehicles

Autonomous vehicles sense their surroundings and drive with little or no human input. Covers sensors, the driving stack, SAE levels, and deployments.
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