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Artificial Intelligence Glossary

Artificial Intelligence (AI) is rapidly growing, with new terms and concepts being introduced at a breakneck speed. You may have seen terms such as AGI, machine learning, or foundation models in media headlines, emerging legislation, or in your everyday life.

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This index of AI terms and definitions is meant to help navigate the world which is constantly being influenced by AI topics.

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AGI (Artificial General Intelligence)

AGI stands for Artificial General Intelligence, which means an AI system with general, human-level (or beyond) ability to learn, reason, and apply knowledge across a wide range of tasks and domains.

Agentic AI

Agentic AI refers to AI systems designed to act as autonomous or semi-autonomous agents: they can set or interpret goals, plan and sequence actions, use tools (like web browsers, code, or APIs), make decisions based on feedback, and adapt over time to complete tasks.

AI Alignment

AI Alignment means making sure an AI system’s goals and behavior match what people actually want—our values, rules, and intentions.

AI Benchmarks

AI Benchmarks are standardized tests used to measure and compare how well AI systems perform on specific tasks, like answering questions, recognizing images, writing code, or following instructions.

AI Safety

AI Safety is the field focused on ensuring AI systems behave reliably and don’t cause harm, even when they’re powerful, widely deployed, or operating in unexpected situations.

Algorithm

An Algorithm is a set of step-by-step instructions for solving a problem or completing a task, similar to a recipe.

Artificial Intelligence (AI)

Artificial Intelligence (AI) is a term coined in 1955 by John McCarthy, Stanford's first faculty member in AI, who described it as "the science and engineering of making intelligent machines."

Attention Mechanism

An Attention Mechanism is a method in neural networks that helps a model focus on the most relevant parts of the input when producing an output.

Backpropagation

Backpropagation is how neural networks learn from mistakes by working backward through the network to figure out which parts caused the error.

Bayesian Networks

Bayesian Networks are graphical models that represent cause-and-effect relationships between variables using probabilities, like a map showing how different factors influence each other.

Bias (in AI)

Bias in AI occurs when a system produces results that favor or discriminate against certain groups of people.

Big Data

Big Data is extremely large datasets, too large to be analyzed by traditional data-processing software, that can be analyzed using AI to reveal patterns and trends.

Chatbot

A Chatbot is a computer program designed to simulate conversation with humans, typically through text or voice interactions.

Closed Source

Also called proprietary software, Closed Source refers to software whose underlying code is restricted and not available for the public to view, modify, or use.

Computer Vision

Computer Vision is a field of AI that enables computers to see, identify, and understand visual information from images and videos, similar to how humans see and process this information.

Context Window

Context Window is the is the amount of input (like text) that an AI system can process at one time during a task.

Contrastive Learning

Contrastive Learning is a machine learning technique where the model learns by comparing similar and dissimilar examples to understand what makes things alike or different.

Data Augmentation

Data Augmentation is a technique to artificially expand a training dataset by creating modified versions of existing data without collecting anything new.

Data Mining

Data Mining is the process of discovering patterns and trends in large datasets using statistical methods and machine learning.

Decision Tree

A Decision Tree is a machine learning algorithm that makes predictions by asking yes/no questions, splitting data at each step based on different features until reaching a final conclusion.

Deep Learning

Deep Learning is a subset of machine learning that uses large multi-layer neural networks to automatically learn complex patterns from data.

Diffusion Models

Diffusion Models are a type of generative model that creates new content like images by adding and then subtracting “noise.”

Dimensionality Reduction

Dimensionality Reduction is a technique for simplifying complex data by reducing the number of variables while preserving the most important information.

Embeddings

Embeddings are numerical representations that convert complex data (like words, images, or other objects) into vectors of numbers that capture their meaning or characteristics.

Ensemble Methods

Ensemble Methods are machine learning techniques that combine multiple models (often called "weak learners") to produce a single, more accurate and robust prediction than any individual model could achieve alone.

Ethical AI

Ethical AI is the design, development, and deployment of artificial intelligence systems that align with human values, fairness, transparency, and societal well-being.

Expert System

Expert Systems are AI programs designed to mimic the decision-making abilities of human experts in specific domains by using a knowledge base of facts and a set of logical rules to draw conclusions, mainly using if-then rules.

Explainable AI (XAI)

Explainable AI (XAI) are methods and techniques that make AI systems' decisions and predictions understandable and interpretable to humans, rather than operating as opaque "black boxes."

Federated Learning

Federated Learning is a machine learning approach where a model is trained across multiple decentralized devices or servers that hold local data, without the data ever leaving its original location.

Few-Shot Learning

Few-Shot Learning is a machine learning approach where models can learn to recognize or perform new tasks with only a small number of training examples.

Fine-tuning

Fine-Tuning is the process of taking a pre-trained model and further training it on task or domain specific data. I

Foundation Model

Foundation Models are large-scale AI models, often transformers, trained on vast amounts of broad, diverse data that can be adapted to perform a wide variety of downstream tasks, serving as a "foundation" for many different applications.

Generative AI

Generative AI (or GenAI) refers to AI systems that can create new content like text, images, music, code, or video.

Generative Adversarial Networks (GANs)

GANs (Generative Adversarial Networks) are a type of AI architecture consisting of two neural networks - a “generator” and a “discriminator” - that compete against each other in a process to create realistic synthetic data.

Generative Pre-Trained Transformer (GPT)

Generative Pre-Trained Transformer (GPT) is a family of large language models developed that uses the transformer architecture to generate human-like text based on input prompts.

GPU (Graphics Processing Unit)

GPU (Graphics Processing Unit) is a specialized electronic chip originally designed to rapidly render graphics and images by performing many mathematical calculations simultaneously in parallel.

Hallucination (in AI)

Hallucinations in AI refers to instances where an artificial intelligence system generates information or responses that are incorrect, misleading, or entirely fabricated but presented as factual.

Human-Centered AI

Human-Centered Artificial Intelligence (HAI) is an approach to AI that prioritizes human needs, values, and well-being throughout the development and deployment of AI systems.

Human-Computer Interaction (HCI)

Human-Computer Interaction (HCI) is the process through which people operate and engage with computer systems.

Human-in-the-loop

Human-in-the-Loop refers to AI systems that include human feedback or intervention as part of their operation.

Hyperparameter

A Hyperparameter is a parameter whose value is set before the learning process of a machine learning model begins.

Inference

In artificial intelligence, Inference is when a trained AI model makes predictions or decisions on new data it hasn't seen before.

Interpretability

Interpretability refers to the degree to which humans can understand how an AI system arrives at its decisions or predictions.

k-Nearest Neighbors (k-NN)

k-NN is a simple, intuitive machine learning algorithm used for classification and regression.

Knowledge Graph

A Knowledge Graph is a structured database that represents information as a network of interconnected entities and their relationships.

Large Language Model (LLM)

A Large Language Model is an AI system trained on massive amounts of text data to understand and generate human-like language.

Latent Space

Latent Space is a compressed, abstract representation where high-dimensional data (like images, text, or audio) is encoded into a lower-dimensional mathematical space that captures the essential features and patterns.

LLMOps

Large Language Model Operations (LLMOps) is the practice of managing the entire lifecycle of LLM-based applications in production environments.

Loss Function

A Loss Function (also called a cost function or objective function) is a mathematical measure that quantifies how wrong a machine learning model's predictions are compared to the actual correct values.

Machine Learning (ML)

Machine Learning is a branch of artificial intelligence that enables computers to learn patterns and make decisions from data without being explicitly programmed with rules.

Markov Chain

A Markov Chain is a mathematical model that describes a sequence of events where the probability of each future event depends only on the current state, not on the history of how you got there.

MLOps

Machine Learning Operations (MLOps) is a set of practices that combines machine learning, software engineering, and DevOps to deploy, monitor, and maintain ML models reliably in production environments.

Model

A Model is a simplified mathematical or computational representation of a real-world system, process, or relationship that is used to make predictions or understand patterns.

Model Drift

Model Drift occurs when a machine learning model's performance degrades over time because the real-world data it encounters has changed from the data it was originally trained on.

Multimodal AI

Multimodal AI refers to artificial intelligence systems that can process, understand, and generate multiple types of data modalities simultaneously—such as text, images, audio, and video.

Natural Language Processing (NLP)

Natural Language Processing (NLP) is a branch of artificial intelligence focused on enabling computers to understand, interpret, and generate human language in a meaningful way.

Neural Network

A Neural Network is a computational model inspired by the structure of the human brain, consisting of interconnected layers of artificial "neurons" that process and transmit information.

Optimization Algorithm

An Optimization Algorithm is a method that helps a machine learning model get better by adjusting its settings to make fewer mistakes.

Overfitting

Overfitting happens when a model memorizes the training data too closely, including mistakes and random patterns.

Open-Weight Model

An Open-Weight Model is an AI model whose core components are publicly released, allowing anyone to download it.

Open Source

Open Source refers to software where its original design, or "blueprint," is made freely available for anyone to see and use.

Parameter

A Parameter is an internal variable within a machine learning model that is learned and adjusted during the training phase.

Predictive Analytics

Predictive Analytics is the practice of using data, statistical methods, and machine learning models to forecast future outcomes or trends.

Prompt Engineering

Prompt Engineering is the practice of carefully crafting instructions, or "prompts," to guide AI language models toward producing desired outputs.

Prompt Injection

Prompt Injection is a type of security attack that uses malicious input to trick a Large Language Model (LLM) into behaving in an unintended way.

RAG (Retrieval-Augmented Generation)

Retrieval-Augmented Generation (RAG) is a technique that helps language models generate higher-quality outputs by allowing them to look up external, up-to-date information first.

Reasoning Model

A Reasoning Model is a type of AI system designed to solve complex problems by generating a logical, step-by-step sequence of thought.

Reinforcement Learning

Reinforcement Learning is a type of machine learning where an AI agent improves its performance through trial and error by taking actions within a specific setting.

Responsible AI

Responsible AI refers to the frameworks, principles, and practices that guide the ethical and safe development and deployment of artificial intelligence systems.

Robotics

Robotics is the field that combines engineering and computer science, and now often artificial intelligence, to design and build machines capable of performing physical tasks.

Spatial Intelligence

Spatial Intelligence is the ability to understand and reason about the three-dimensional physical world, including how objects relate to each other in space, how they move, and how they interact.

Self-Supervised Learning

Self-Supervised Learning is a training method where an AI model teaches itself by creating its own puzzles from raw data and then trying to solve them.

Semantic Analysis

Semantic Analysis is the process of understanding the meaning of language by examining the relationship between words, phrases, and symbols.

Scaling Laws

Scaling Laws are predictable mathematical relationships that describe how AI model performance improves as factors like model size, training data, and computing power increase.

Supervised Learning

Supervised Learning is a machine learning approach where models are trained on labeled data—input examples paired with correct output answers.

Synthetic Data

Synthetic Data is artificially generated information created by algorithms or simulations rather than collected from real-world events or observations.

Tensor

A Tensor is essentially a container for numbers organized in multiple dimensions, like a more advanced version of a spreadsheet.

Tokenization

Tokenization is the process of breaking down text into smaller units called tokens—which can be words, parts of words, or even individual characters—that AI language models can process.

Traditional AI

Traditional AI refers to earlier approaches to artificial intelligence that relied on explicitly programmed rules, logic, and human-defined knowledge rather than learning from data.

Training Data

Training Data is the collection of examples—such as text, images, audio, or other information—used to teach machine learning models how to perform specific tasks.

Transfer Learning

Transfer Learning is a machine learning technique where a model trained on one task is reused as the starting point for a different but related task.

Transformer

A Transformer is a neural network architecture that revolutionized AI by using a mechanism called "attention" to process and understand relationships between all parts of input data simultaneously, rather than sequentially.

Turing Test

The Turing Test, proposed by mathematician Alan Turing in 1950, is a measure of a machine's ability to exhibit intelligent behavior indistinguishable from a human.

Unsupervised Learning

Unsupervised Learning is a machine learning approach where models are trained on data without labeled answers or predefined categories, tasked with finding patterns and structure on their own.

Vector Database

A Vector Database is a specialized type of database designed to store and efficiently search through high-dimensional numerical representations (vectors) of data like text, images, or audio.

Vision Transformer (ViT)

A Vision Transformer (ViT) is an adaptation of the transformer architecture, originally designed for language, to process and analyze images.

Weights

Weights are the numerical parameters within a neural network that determine the strength of connections between artificial neurons and ultimately shape how the model processes information.

Zero-Shot Learning

Zero-Shot Learning is the ability of an AI model to perform tasks or recognize categories it has never been explicitly trained on, using only its general knowledge and understanding.