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.
Support Vector Machines (SVM)
A classifier that separates two classes with the widest possible margin, using support vectors and the kernel trick to handle non-linear data.
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.
High Bias
Statistical bias, not AI fairness: the error a model class cannot escape even with infinite data — worked in closed form on a line fitted to a parabola.
Chunking
Chunking splits documents into smaller passages before embedding them for retrieval. Chunk size, overlap, and splitting strategy quietly decide RAG quality.
Large Language Model (LLM)
A large language model predicts the next token of text. How that produces answers, where its knowledge is stored, and why an LLM is not a chatbot.
Matrix Multiplication (GEMM)
The one operation that consumes most of an AI model's compute — and the reason AI chips are built the way they are, from tensor cores to systolic arrays.
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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