# Glossary ### Merchant An individual or organization with access to Inqud's API and authorized to use the On-Ramp API. ### User Or end user (interchangeably), a customer of a merchant who will pay for the merchant's services or goods. ### Project A core entity of on-ramp, linking all operations within its scope. Merchants can create checkouts for users, setup notification about its status. ### Checkout An invoice with a specified amount, which can be in any currency. Users can open checkout page and perform a payment. Inqud handles the conversion between the checkout currency and the user-pay currency. At the moment merchant receives funds in USDC.\ \ Checkouts outs can be of two types: FIXED\_PRICE (with a specified amount) and NO\_PRICE (without a specified amount). ### Payment A payment refers to an actual incoming transaction processed by Inqud, which is visible on the Wallets page in the user's Cabinet. ### Callback/Webhook A notification sent by the Inqud system to the merchant's backend to propagate information about checkouts. Callbacks enable real-time updates on payment status and other transaction-related events. --- # 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://docs.inqud.com/on-ramp/glossary.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.