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.
Ambient Clinical Documentation
AI scribes draft the clinical note from consultation audio. What the largest deployment and the randomised trials measured — and who stays liable.
Knowledge Distillation
How a small model learns what a big one knows: the teacher's full probability distribution carries structure the hard labels do not — Hinton's dark knowledge.
Underfitting
Underfitting is when a model is too simple to capture the real pattern, so it does poorly on both training and new data — the mirror of overfitting.
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.
Voice Recognition
How AI turns spoken words into text (speech recognition / ASR) — and how that differs from identifying who is speaking (speaker recognition).
Deep Learning
What makes deep learning deep: each layer builds on the one below, so capacity grows multiplicatively with depth and only additively with width.
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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