# Mastercard Gateway API Reference Documentation - REST source: https://developer.mastercard.com/mastercard-gateway/documentation/api-reference/v100/rest/index.md From API version 100, integrations must be able to handle [non-breaking](https://developer.mastercard.com/mastercard-gateway/documentation/versioning/index.md) changes. Any API References for deprecated versions are hidden. For information on all API versions, see our [changelog](https://gateway.mastercard.com/api/documentation/apiDocumentation/rest-json/version/100/changelog.html?locale=en_US). ## Understanding the Mastercard Gateway API {#understanding-the-mastercard-gateway-api} Whether you are a coding maestro or just starting out, our intuitive interface and robust API have been meticulously crafted to ensure that integrating payments into your applications is not only efficient but downright enjoyable. ### Agreement {#agreement} Allows the merchant to store the payer's payment details and make payments under that agreement without the payer's involvement. View Documentation ### Authentication {#authentication} Authentication process to confirm the identity of the payer attempting to make a transaction. View Documentation ### Batch {#batch} Submit batches of operations (Captures, Refunds, and so on) to the Gateway for processing without direct payer interaction. View Documentation ### Browser Payment {#browser-payment} Browser payment methods allow a payer to pay for goods and services online on the browser payment provider's website. View Documentation ### Gateway {#gateway} Operations related to speaking directly to the Gateway for status or payment option-related details. View Documentation ### Hosted Checkout {#hosted-checkout} Request to initiate a Hosted Checkout interaction. View Documentation ### Payment Plan {#payment-plan} Request to retrieve a set of payment plan offers for a payment plan so that they can be presented to the cardholder. View Documentation ### Session {#session} A payment session, or simply session, is a temporary container for any request fields and values of operations that reference a session. View Documentation ### Standalone Risk Assessment {#standalone-risk-assessment} Standalone risk assessment is for routing a card transaction to a risk service provider for risk assessment without processing a payment. View Documentation ### Tokenization {#tokenization} The identifier for the stored card details that may be used for later to refer to the card details to perform a payment or authorization. View Documentation ### Transaction {#transaction} Represents a request by a merchant to transfer money (or to prepare for the transfer) between a payer's account and the merchant's account (or vice versa). View Documentation ### Wallet {#wallet} An electronic service that allows payers to securely store payment details (for example credit card details). View Documentation ## SDKs {#sdks} ### Checkout {#checkout} The JavaScript library allows simple payment integrations for merchant sites. View Documentation ### Click to Pay {#click-to-pay} The JavaScript library allows you to add support for Click to Pay to your payment page. View Documentation ### PayPal {#paypal} A JavaScript-based, client-side SDK for PayPal payments. View Documentation ### Risk {#risk} JavaScript based client-side SDK for integration with NuDetect risk assessment platform. View Documentation ### Rupay {#rupay} JavaScript based client-side SDK for Rupay authentication flows for online payments. View Documentation ### Session {#session} The JavaScript library allows you to collect sensitive payment details from the payer in fields hosted by the gateway. View Documentation ### ThreeDS {#threeds} A JavaScript-based client-side SDK for EMV 3-D Secure authentication flows for online payments. View Documentation