eXtensible Markup Language - a markup language for storing and transporting structured data. Like HTML but designed for data instead of web pages.
Bank systems often exchange transaction data using XML format because it's both human-readable and machine-readable.
XML is an open, vendor-neutral data format (a W3C standard), not a cloud service. All major cloud providers support storing, validating, transforming, and processing XML using their general compute, storage, integration, and database services (for example: object storage for XML files, serverless functions for parsing, and API gateways for XML-based integrations).