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.
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.
Vision Transformer (ViT)
A Vision Transformer (ViT) cuts an image into fixed patches, embeds each as a token, and runs a transformer encoder — trading CNN inductive bias for scale.
Social AI
Social AI is artificial intelligence built to perceive, interpret, and take part in human social interaction — reading emotion, tone, intent, and context.
Privacy
In AI, privacy is about what a model can memorize and leak about people, and the techniques—differential privacy, federated learning—that limit it.
Feature Selection (FS)
Which columns to keep and how to decide: filter vs wrapper vs embedded, why 2^n subsets rules out brute force, and the CV mistake that fakes accuracy.
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.
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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