Learn artificial intelligence

A clear encyclopedia for AI concepts — systems, models, evaluation, safety, and how tools fit together — organized by branch so you can start where you are and go deeper without a wall of cards.

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Fundamentals

What AI is, how it differs from automation, and the core vocabulary.

  • AI Inference

    Inference is running a trained model on new inputs to produce predictions or generations—the production phase users experience when they chat, search, or…

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  • AI Training

    AI training is the process of adjusting model parameters using data and an optimization objective so the model improves at predicting or generating target…

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  • Artificial General Intelligence

    Artificial general intelligence (AGI) refers to AI systems that can learn and perform most intellectual tasks at a level comparable to humans across…

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  • Artificial Intelligence

    Artificial intelligence (AI) is the field of computer science that builds systems capable of performing tasks that typically require human cognitive…

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  • Model Parameters

    Model parameters are the learned numeric values—weights and biases—that a neural network adjusts during training so it can map inputs to useful outputs.

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  • Narrow AI

    Narrow AI (also called weak AI) refers to systems designed for specific tasks—translation, image classification, coding assistance—rather than general…

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  • Symbolic AI

    Symbolic AI represents knowledge with explicit symbols and rules—logic, knowledge graphs, expert-system style reasoning—complementing statistical machine…

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Machine Learning

Learning from data: supervised, unsupervised, evaluation, and classic models.

  • Classification

    Classification is a supervised learning task that assigns inputs to discrete categories, such as spam vs. not-spam or disease present vs. absent.

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  • Clustering

    Clustering groups unlabeled examples by similarity so you can discover segments, structure, or candidates for further labeling.

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  • Cross-Validation

    Cross-validation estimates how well a model generalizes by repeatedly training and evaluating on different splits of the data.

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  • Feature Engineering

    Feature engineering transforms raw data into inputs that make learning easier—ratios, encodings, windows, and domain-derived signals that improve model…

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  • Gradient Descent

    Gradient descent optimizes model parameters by repeatedly stepping opposite the gradient of the loss, forming the backbone of modern deep learning training.

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  • Hyperparameters

    Hyperparameters are training and model choices set before learning parameters—learning rate, batch size, depth, and regularization strength among them.

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  • Loss Functions

    A loss function quantifies how wrong a model’s prediction is so optimizers can update parameters to improve performance.

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  • Machine Learning

    Machine learning (ML) is a set of methods that improve a model’s performance on a task by learning patterns from data rather than relying solely on…

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  • Overfitting

    Overfitting happens when a model memorizes training data quirks and fails to generalize to new data, producing optimistic offline scores and disappointing…

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  • Reinforcement Learning

    Reinforcement learning (RL) is a machine learning paradigm where an agent learns to make sequential decisions by interacting with an environment and maximizing…

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  • Self-Supervised Learning

    Self-supervised learning creates training signals from the data itself—such as predicting masked words or corrupted patches—so models learn representations…

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  • Supervised Learning

    Supervised learning trains models on input–label pairs so they can predict labels for new inputs—classification and regression are the classic cases.

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  • Unsupervised Learning

    Unsupervised learning finds structure in unlabeled data—clusters, densities, compressed representations—without predefined target labels.

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Deep Learning

Neural networks, layers, representation learning, and modern training.

  • Attention

    Attention mechanisms let neural networks weight which parts of an input sequence are most relevant when computing each output representation or token.

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  • Backpropagation

    Backpropagation computes gradients of the loss with respect to neural network parameters efficiently, enabling gradient-based training of deep models.

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  • Computer Vision

    Computer vision is the AI field that enables machines to interpret images and video—detecting objects, estimating pose, reading text in scenes, segmenting…

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  • Convolutional Neural Networks

    Convolutional neural networks (CNNs) use local filters and weight sharing to learn spatial hierarchies—foundational for modern computer vision.

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  • Deep Learning

    Deep learning is a machine learning approach that uses multi-layer neural networks to learn hierarchical representations from data. It powers modern speech…

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  • Embeddings

    Embeddings are vector representations of text, images, or other objects that place similar items nearby in a geometric space for search, clustering, and model…

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  • Neural Networks

    Neural networks are computational models composed of interconnected units (neurons) that transform inputs through weighted connections and nonlinear…

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  • Transformers

    Transformers are neural architectures that use attention mechanisms to model relationships among tokens, forming the backbone of modern language, vision, and…

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Generative AI

Systems that produce text, images, audio, and other media.

  • Foundation Models

    Foundation models are large pretrained models adaptable to many downstream tasks via prompting, fine-tuning, or tooling—central to today’s AI product ecosystem.

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  • Generative AI

    Generative AI refers to models that create new content—text, images, audio, code, or other media—by learning the patterns of a training distribution. It…

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  • Multimodal Models

    Multimodal models accept or produce more than one data type—such as text, images, audio, or video—within a unified or coordinated architecture.

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LLMs

Large language models, transformers, tokenization, and prompting basics.

  • Context Windows

    A context window is the maximum amount of text (tokens) a language model can consider at once—including the system prompt, user messages, retrieved documents…

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  • Fine-Tuning

    Fine-tuning adapts a pretrained model to a target task, domain, or style by continuing training on curated examples—often with parameter-efficient methods.

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  • Large Language Models

    Large language models (LLMs) are neural networks trained on vast text corpora to predict tokens in context, enabling fluent generation, summarization…

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  • Natural Language Processing

    Natural language processing (NLP) is the AI subfield that enables computers to analyze, generate, and interact through human language. It spans classical…

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  • Pretraining

    Pretraining is large-scale learning on broad data that builds general model capabilities before any task-specific fine-tuning or product alignment.

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  • Quantization

    Quantization reduces numeric precision of model weights (and sometimes activations) to cut memory and accelerate inference with controlled quality loss.

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  • Reasoning Models

    Reasoning models are language models trained or configured to spend more test-time computation on multi-step problem solving, often with explicit intermediate…

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  • RLHF

    Reinforcement Learning from Human Feedback (RLHF) shapes model behavior using preference data and reward models rather than only static supervised targets.

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  • Temperature

    Temperature is a decoding parameter that scales next-token probabilities, influencing how deterministic or varied a language model’s outputs are.

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  • Tokens

    Tokens are the discrete units language models read and generate—commonly subword pieces—used for context limits, billing, and model input encoding.

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  • Tool Calling

    Tool calling lets models request structured actions—search, calculators, CRM updates, code execution—through well-defined function interfaces rather than…

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Agents

Tool-using loops, planning, memory, and grounded autonomy.

  • AI Agents

    AI agents are systems that use models to pursue goals through multi-step reasoning and actions—often calling tools, browsing information, writing files, or…

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  • Human in the Loop

    Human-in-the-loop (HITL) designs keep people involved in training, review, or approval so AI systems stay accountable and correctable.

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  • Multi-Agent Systems

    Multi-agent systems coordinate multiple AI (and sometimes human) agents with different roles or tools to complete complex workflows.

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Media

Vision, speech, video, and multimodal pipelines.

  • AI Image Generation

    AI image generation creates new pictures from text prompts, reference images, or editing instructions. Modern systems often use diffusion models and are widely…

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  • AI Video Generation

    AI video generation synthesizes short clips from text, images, or existing footage using generative models. Products differ in duration limits, motion…

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  • Diffusion Models

    Diffusion models are a generative modeling family that learn to reverse a gradual noising process. They underpin many modern image and video generators and are…

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  • Speech to Text

    Speech-to-text (STT), or automatic speech recognition (ASR), converts spoken audio into written text. It powers captions, meeting notes, voice interfaces, and…

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  • Text to Image

    Text-to-image systems generate pictures from natural-language prompts, typically using diffusion or related generative models trained on image–text pairs.

    beginner
  • Text to Speech

    Text-to-speech (TTS) systems convert written text into audible speech. Modern neural TTS can sound natural across languages and styles, powering accessibility…

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  • Voice Cloning

    Voice cloning synthesizes speech that resembles a specific person’s voice, usually from reference audio samples plus text-to-speech models.

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RAG & Search

Embeddings, retrieval-augmented generation, and grounded answers.

  • Chunking

    Chunking splits documents into smaller passages before embedding and retrieval so models receive focused, relevant context.

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  • Retrieval-Augmented Generation

    Retrieval-augmented generation (RAG) combines a language model with a search or retrieval step so answers can cite or incorporate external documents. It is a…

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  • Semantic Search

    Semantic search retrieves information by meaning using embeddings and similarity, rather than relying only on exact keyword matches.

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  • Vector Databases

    Vector databases store embedding vectors and support approximate nearest neighbor search so applications can retrieve semantically similar items at scale.

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Prompting

Instructions, few-shot patterns, and evaluation of prompt quality.

  • Chain-of-Thought Prompting

    Chain-of-thought (CoT) prompting encourages models to work through intermediate steps on multi-step problems, improving some reasoning benchmarks when used…

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  • Few-Shot Prompting

    Few-shot prompting includes a handful of example input–output pairs in the prompt so the model can imitate the demonstrated pattern.

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  • Prompt Engineering

    Prompt engineering is the practice of designing instructions, examples, and context so generative models produce more reliable results. It ranges from everyday…

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  • Prompt Injection

    Prompt injection is an attack where untrusted content manipulates an AI system into ignoring developer instructions or misusing tools.

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  • System Prompts

    System prompts are higher-priority instructions that set an AI assistant’s role, style, tool policies, and safety constraints for a session or application.

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  • Zero-Shot Prompting

    Zero-shot prompting asks a model to perform a task using instructions alone, without providing worked input–output examples in the prompt.

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Building with AI / Development

APIs, evaluation harnesses, product integration, and ops concerns.

  • AI APIs

    AI APIs expose model capabilities—chat, embeddings, speech, images, and more—over programmatic interfaces so developers can integrate intelligence into…

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  • Function Calling

    Function calling is the API pattern where models return structured arguments for developer-defined functions, enabling reliable tool use from LLMs.

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  • Local AI

    Local AI runs models on devices or private infrastructure you control, reducing reliance on third-party cloud inference for privacy, offline use, or cost…

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  • Open-Weight Models

    Open-weight models release learned parameters for download and local or self-hosted inference, with licenses that may still restrict some commercial uses.

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Responsible AI

Safety, bias, privacy, copyright, and trustworthy deployment.

  • AI Alignment

    AI alignment research and practice aim to make AI systems pursue intended goals and constraints—matching human/organizational preferences and safety…

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  • AI Copyright

    AI copyright issues involve training on protected works, ownership of model outputs, licensing of datasets and weights, and evolving official guidance that…

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  • AI Detection

    AI detection tools estimate whether text, images, audio, or video were produced or altered by generative models—estimates that are inherently probabilistic and…

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  • AI Governance

    AI governance is the system of policies, roles, controls, and oversight processes organizations use to manage AI risk, compliance, and value delivery.

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  • AI Hallucinations

    AI hallucinations are confident but incorrect model outputs—especially fabricated facts, sources, or details—produced by generative systems. Understanding why…

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  • AI Privacy

    AI privacy covers how personal data is collected, used in training and inference, retained in logs/prompts, and protected against leakage through model outputs…

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  • AI Safety

    AI safety covers technical and organizational practices that reduce harmful outcomes from AI systems—ranging from misuse and accidents today to longer-term…

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  • Bias in AI

    Bias in AI refers to systematic error or unfair differential performance that harms people or distorts decisions, often reflecting data, design, or deployment…

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  • Deepfakes

    Deepfakes are synthetic media—video, audio, or images—that convincingly depict people saying or doing things they did not, enabled by generative AI.

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  • Explainable AI

    Explainable AI (XAI) aims to make model behavior understandable to humans through interpretable models, post-hoc explanations, or evidence-centered product…

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Practice

Hands-on exercises and applied drills tied to encyclopedia topics.

  • AI Coding Assistants

    AI coding assistants help developers write, edit, explain, and refactor software by combining large language models with editor or repository context. They…

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History

Milestones that shaped research and products.

  • History of AI

    The history of artificial intelligence spans symbolic reasoning and early expert systems, winters of reduced funding, the statistical and deep learning…

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Comparisons

Side-by-side concept contrasts without marketing fluff.

  • AI vs Machine Learning

    Artificial intelligence is the broader field of creating systems that perform tasks associated with intelligence; machine learning is a major approach that…

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  • Machine Learning vs Deep Learning

    Deep learning is machine learning with multi-layer neural networks that learn hierarchical features, especially effective for unstructured data like images…

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  • Open Source vs Open-Weight AI

    Open-source AI typically implies publicly licensed code (and often training recipes) under OSI-style terms, while open-weight AI releases model parameters…

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  • RAG vs Fine-Tuning

    RAG connects models to external evidence at query time; fine-tuning changes model weights to learn behaviors or styles from curated datasets.

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  • RAG vs Long Context

    Long-context models can read large prompts directly; RAG selectively retrieves relevant snippets so the model is not forced to read an entire corpus every time.

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  • Text to Speech vs Speech to Text

    Text-to-speech (TTS) turns written text into audio; speech-to-text (STT) turns audio into written text. They are inverse interface problems with different…

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  • Training vs Inference

    Training learns parameters from data; inference applies a trained model to new inputs to produce predictions or generations.

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Learning Paths

Ordered lesson sequences — no account required.

  • AI for Beginners

    A gentle path from basic AI concepts to practical tools—without assuming a math background.

    Curious beginners, students, and professionals new to AI
  • How LLMs Work

    From tokens and transformers to grounding strategies used in real LLM applications.

    Students, developers, and technical PMs
  • Generative Media

    Learn image, video, and voice generation systems—and the responsible-use practices they require.

    Creators, marketers, and product teams
  • Building with AI

    A builder’s path through APIs, prompting, retrieval, agents, and deployment choices including local models.

    Developers and technical founders

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Glossary

Quick A–Z definitions linked back into encyclopedia topics.

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Concept Map

See how AI, machine learning, deep learning, LLMs, RAG, and agents relate.

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