# Glossary

### Merchant

An individual or organization with access to Inqud's API and authorized to use the Crypto Acquiring API.

### User

Or end user (interchangeably), a customer of a merchant who will pay in cryptocurrency for the merchant's services or goods.

### Project (Widget)

A core entity of crypto acquiring, linking all operations within its scope. Merchants can select cryptocurrencies available for payment and configure auto exchange settings for each project.

### Auto-Convert

After a user sends money to the address specified in the request, Inqud processes the payment and automatically creates an exchange order according to the configured auto exchange rules.

### Domain

The domain of a merchant's website, necessary for adding the crypto widget.

### Crypto Widget

An embeddable component that merchants can place on their websites to facilitate cryptocurrency payments.

### Checkout

An invoice with a specified amount, which can be in fiat currency. Users can select their preferred cryptocurrency within the scope of the checkout and create a request. Inqud handles the conversion between the checkout currency and the user-selected currency.\
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Checkouts outs can be of two types: FIXED\_PRICE (with a specified amount) and NO\_PRICE (without a specified amount). 

Checkout can have only one request linked to it.

### Request

A demand for payment, specifying a certain amount of a particular cryptocurrency.

Requests can be of two types: FIXED\_PRICE (with a specified amount) and NO\_PRICE (without a specified amount).

Request can have only one payment linked to it.

### Payment

A payment refers to an actual incoming blockchain 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 payment requests or checkouts. Callbacks enable real-time updates on payment status and other transaction-related events.

### Callback (JavaScript)

In the context of a Crypto Widget, a Callback is a JavaScript function that is passed to the widget to handle events related to checkout status transitions. This function is invoked whenever there is a change in the checkout status. The Callback allows for efficient and real-time management of user interactions and payment processes within the Crypto Widget, providing developers with greater control and flexibility in handling transaction events.