Look up any term in AI.
Definitions that explain the actual mechanism — not a paraphrase of the name. Written for people who have to build with this, or decide about it.
Glossary
256 terms, each with a worked definition, how it actually works, and where it breaks.
Browse A–ZModels
What each model is good at, what it costs per token, and when the size matters.
Compare modelsAI tools
68 tools across 11 categories, with pricing and status kept current.
Browse the directoryExplainers
Longer pieces on the things a definition cannot hold: benchmarks, costs, and claims worth checking.
Read the blogStart with the load-bearing ideas
The terms the rest keep referring back to. Read these and most AI writing stops being opaque.
Human-AI Collaboration (HAC)
Splitting one task between a person and a model. A meta-analysis of 106 experiments found the pair usually loses to whichever of the two is better alone.
GPU Computing
Why a graphics chip runs AI: a GPU spends its transistors on arithmetic instead of on making one thread fast — and what that trade wins and costs.
Generalization
Why a model that scores 99% in training fails in the world: the generalization gap, the test-set size needed to measure it, and why classical theory is wrong.
Autonomous Systems
Automation runs a procedure someone wrote down; autonomy picks the procedure at run time. Sense-plan-act loops, operational design domains and autonomy levels.
Semiconductor Manufacturing
How an AI chip is actually made — wafers, process nodes, yield and the foundry model — and why supply cannot simply respond to a spike in demand.
Ethics in AI
AI ethics is what happens when good principles provably conflict: fairness against fairness, privacy against accuracy, and whose values get to decide.
Recently updated tools
Every listing carries a status. When a product is renamed, sunset or acquired, the page says so.
AgentGPT
Reworkd AI · Web Application
Open-source, browser-based autonomous AI agent from Reworkd. You name a goal, the agent plans tasks, executes them, and learns from the results.
FreemiumDola (formerly Cici)
ByteDance · Web, Mobile & Desktop Application
ByteDance's overseas AI assistant, renamed from Cici in November 2025. Free chat, translation and image generation, region-locked out of the US and China.
FreeKimi Code
Moonshot AI · CLI Tool & Editor Integration
Moonshot AI's open-source terminal coding agent: an MIT-licensed CLI with MCP and editor integration, driving Kimi K3 and K2.7 Code via Kimi membership.
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