AI reference

Clear AI definitions and model data you can check.

A glossary written for practitioners, research summaries, and language models compared on price, limits and capabilities, with a source and a date next to every number.

255glossary terms
135articles
65models priced
next-token-prediction.py

Glossary

255 terms · A–Z

Definitions first, then how it works, worked examples, formulas and code.

LLM API pricing

65 models · 5 vendors

Per-token prices from each vendor's own page, with cache, batch and long-context rates.

Models

10 model cards · 9 comparisons

Context windows, limits and capabilities, with the source behind each value.

Tools

Token counter · cost calculator

Count the tokens in your prompt, then see what a month of traffic costs on every model.

LLM changelog

27 changes · last Oct 14, 2026

Model launches, price changes and retirements, each linked to the vendor's notice.

News and research

135 articles

Pricing news, research summaries and applied machine learning explainers.

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AI Education

How Does AI Work? A Plain-English Guide, From Training to the Answer on Your Screen

How does AI work? Most modern artificial intelligence learns patterns from huge numbers of examples, then uses those patterns to predict: the next word, the likely label, the best move. It doesn't follow a rule book for every situation,…