# Core Concepts The Grid is a real-time spot market for AI inference - a single venue where developers buy standardized inference capacity from competing suppliers through an OpenAI-compatible API. \ \ The system is built on a few fundamental ideas: standardized contracts called Instruments that define quality guarantees, atomic quantities called Units that you trade and consume, and a dual-account system that separates financial ownership from active usage. * [**Instruments**](https://thegrid.ai/docs/introduction/core-concepts/instruments) - Describes the standardized contracts that guarantee a minimum intelligence, latency, throughput, and context window for delivered inference. * [**Units**](https://thegrid.ai/docs/introduction/core-concepts/units) **-** Explains the atomic 1M-token building block of capacity that you trade on the exchange and consume through the API. * [**Trading and Consumption Accounts**](https://thegrid.ai/docs/introduction/core-concepts/trading-and-consumption-accounts) - Explains how The Grid separates financial ownership from active usage through two logical balances per Instrument. * [**Lots and the Consumption Window** ](https://thegrid.ai/docs/introduction/core-concepts/lots-and-consumption-window)- Describes how Units are grouped into Lots with a four-hour use-it-or-lose-it window that enforces market discipline. * \[COMING SOON] [**Scheduled Sweeps**](https://thegrid.ai/docs/introduction/core-concepts/scheduled-sweeps) - Explains the every-four-hour process that automatically moves Units from Trading to Consumption and tightly links trading to delivery. * [**Tokens and Metering**](https://thegrid.ai/docs/introduction/core-concepts/tokens-and-metering) - Describes how every API call is tokenized, attributed to specific Lots and Units, and recorded for accurate billing and quality enforcement. * [**Market Participants**](https://thegrid.ai/docs/introduction/core-concepts/market-participants) – Introduces Consumers, Suppliers, and The Grid Market and how each role participates in trading and delivery. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://thegrid.ai/docs/introduction/core-concepts.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.