AWS AI Practitioner study materials
AWS AI Practitioner study resources

AWS AI Practitioner key terms

AWS AI Practitioner · Get comfortable with the vocabulary.

Artificial Intelligence (AI)

The broad field of building computer systems that perform tasks normally requiring human intelligence, such as reasoning, language understanding, perception, and decision-making. It encompasses machine learning, generative AI, and rule-based approaches.

Related: Machine Learning (ML), Generative AI
Machine Learning (ML)

A subset of AI where algorithms learn patterns from data rather than following hand-written rules, then use those patterns to make predictions or decisions on new, unseen data.

Related: Training Data, Inference, Supervised Learning
Supervised Learning

A training approach that uses labeled examples, where each input is paired with the correct answer, so the model learns to map inputs to outputs. Common for classification and regression tasks.

Related: Training Data, Unsupervised Learning, Model Evaluation
Unsupervised Learning

A training approach that works with unlabeled data, letting the algorithm discover structure such as clusters or groupings on its own. Used for segmentation, anomaly detection, and pattern discovery.

Related: Supervised Learning, Clustering
Clustering

An unsupervised technique that groups similar data points together based on shared characteristics, without predefined labels. Useful for customer segmentation, document grouping, and exploratory analysis.

Related: Unsupervised Learning
Reinforcement Learning (RL)

A training paradigm where an agent learns by taking actions in an environment and receiving rewards or penalties, gradually discovering behavior that maximizes cumulative reward. Often used for control and game-playing tasks.

Related: Reinforcement Learning from Human Feedback (RLHF)
Training Data

The dataset used to teach a model its patterns and parameters. Its quality, size, and representativeness strongly influence model accuracy and fairness.

Related: Machine Learning (ML), Bias, Model Evaluation
Inference

The process of using a trained model to produce predictions or outputs on new input data. It happens after training and is what end users typically trigger in production.

Related: Machine Learning (ML), Foundation Model
Model Evaluation

The practice of measuring how well a trained model performs on data it has not seen, using metrics and held-out test sets, to judge accuracy, generalization, and readiness for deployment.

Related: Training Data, Overfitting
Overfitting

When a model learns its training data too closely, including noise, and performs poorly on new data. It signals weak generalization and is often addressed with more data or regularization.

Related: Model Evaluation, Training Data
Generative AI

A category of AI that creates new content such as text, images, audio, or code in response to a prompt, rather than only classifying or predicting labels from existing data.

Related: Foundation Model, Large Language Model (LLM), Prompt
Foundation Model

A large model pretrained on broad data that can be adapted to many downstream tasks through prompting or fine-tuning, instead of being built for a single purpose.

Related: Large Language Model (LLM), Fine-Tuning, Generative AI
Large Language Model (LLM)

A foundation model trained on vast amounts of text to understand and generate language. It predicts likely token sequences and powers tasks like summarization, translation, and question answering.

Related: Token, Foundation Model, Prompt
Token

A small unit of text, such as a word, word fragment, or character, that a language model processes. Token counts drive context limits and often pricing.

Related: Large Language Model (LLM), Context Window
Prompt

The input instruction or question given to a generative model to guide its output. Clear, specific prompts generally produce more relevant and reliable responses.

Related: Prompt Engineering, Large Language Model (LLM)
Prompt Engineering

The practice of designing and refining prompts, including instructions, examples, and formatting, to obtain accurate, relevant, and well-structured responses from a foundation model.

Related: Prompt, Few-Shot Prompting, Retrieval-Augmented Generation (RAG)
Few-Shot Prompting

A prompting technique that includes a small number of worked examples in the prompt so the model can infer the desired format or reasoning pattern before answering the real request.

Related: Prompt Engineering, Zero-Shot Prompting
Zero-Shot Prompting

Asking a model to perform a task with instructions only and no worked examples. It relies on the model's pretrained knowledge and works best for common, well-understood tasks.

Related: Few-Shot Prompting, Prompt Engineering
Context Window

The maximum amount of text, measured in tokens, that a model can consider at one time, including the prompt and its response. Larger windows allow longer documents and conversations.

Related: Token, Retrieval-Augmented Generation (RAG)
Retrieval-Augmented Generation (RAG)

A pattern that retrieves relevant documents from an external knowledge source and adds them to the prompt, so the model answers using current, domain-specific information without retraining.

Related: Embedding, Vector Database, Hallucination
Embedding

A numeric vector representation of text, images, or other data that captures meaning, so items with similar meaning sit close together. Embeddings enable semantic search and retrieval.

Related: Vector Database, Retrieval-Augmented Generation (RAG)
Vector Database

A data store optimized for storing embeddings and quickly finding the most similar vectors to a query. It is a common backing service for retrieval-augmented generation and semantic search.

Related: Embedding, Retrieval-Augmented Generation (RAG)
Fine-Tuning

Further training of a pretrained foundation model on a smaller, task-specific dataset so it adapts to a particular domain, style, or behavior. It is more costly than prompting alone.

Related: Foundation Model, Training Data
Hallucination

When a generative model produces confident but incorrect or fabricated information. It is a key reliability risk and is often mitigated with retrieval, grounding, and human review.

Related: Retrieval-Augmented Generation (RAG), Human-in-the-Loop
Bias

Systematic unfairness in model outputs, often arising from skewed or unrepresentative training data. It can cause discriminatory outcomes and must be measured and mitigated.

Related: Training Data, Fairness
Fairness

The principle that AI systems should treat individuals and groups equitably and avoid discriminatory outcomes. It is assessed through metrics, testing, and diverse data.

Related: Bias, Responsible AI
Explainability

The degree to which people can understand why an AI system produced a given output. It supports trust, debugging, auditing, and accountability in decisions affecting users.

Related: Responsible AI, Human-in-the-Loop
Responsible AI

A set of principles and practices for building AI that is fair, transparent, safe, accountable, and privacy-respecting. It guides design, testing, and monitoring across the model lifecycle.

Related: Fairness, Explainability, Human-in-the-Loop
Human-in-the-Loop

A design where people review, approve, or correct AI outputs at key points. It reduces risk in high-stakes decisions and supports accountability and quality control.

Related: Hallucination, Responsible AI
Guardrails

Configurable controls that constrain model behavior, such as content filters, topic restrictions, and blocked outputs. They help enforce safety, policy, and brand requirements in applications.

Related: Responsible AI, Content Moderation
Content Moderation

Automated or human review that detects and filters harmful, offensive, or policy-violating content in inputs and outputs. It protects users and supports safe deployment of generative applications.

Related: Guardrails
Data Privacy

Protecting personal and sensitive information throughout collection, storage, and processing, including limiting what is shared with AI services and honoring consent and retention rules.

Related: Encryption, Access Control
Encryption

Encoding data so only authorized parties can read it, both while stored and while in transit. It is a core safeguard for protecting sensitive data used by AI systems.

Related: Data Privacy, Access Control
Access Control

Policies and mechanisms that determine who or what can view or use specific resources. Least-privilege access limits exposure of sensitive data and model endpoints.

Related: Data Privacy, Encryption, Identity and Access Management (IAM)
Identity and Access Management (IAM)

The framework for managing user identities and their permissions across systems. In AI workloads it governs who can invoke models, access data, and change configurations.

Related: Access Control, Audit Trail
Audit Trail

A chronological record of system activity, such as who accessed data or invoked a model and when. It supports investigations, compliance reporting, and accountability.

Related: Governance, Identity and Access Management (IAM)
Governance

The policies, roles, and oversight processes that direct how AI systems are approved, monitored, and retired. It aligns AI use with legal, ethical, and organizational requirements.

Related: Audit Trail, Responsible AI
Reinforcement Learning from Human Feedback (RLHF)

A training method that uses human rankings of model outputs to shape a reward signal, then tunes the model toward responses people prefer. It improves helpfulness and alignment.

Related: Reinforcement Learning (RL), Fine-Tuning