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
71models priced
next-token-prediction.py

Glossary

255 terms · A–Z

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

LLM API pricing

71 models · 5 vendors

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

Models

17 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

33 changes · last Oct 26, 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

The History of Artificial Intelligence: From Turing to the LLM Boom

No single person invented artificial intelligence. The name comes from a proposal dated August 31, 1955, written by John McCarthy, Marvin Minsky, Nathaniel Rochester and Claude Shannon. Their workshop at Dartmouth College in the summer of…