XML, or Extensible Markup Language, is a versatile markup language used to store and transport structured data in a human-readable format. It defines a set of rules for encoding documents in a format that is both machine and human-readable, making it widely used in web development, data exchange, and configuration settings. Toronto Website Design Company uses XML for within their web applications. It also facilitates communication between different systems, and streamline data integration processes. By understanding XML's principles and capabilities, the company can enhance the efficiency and flexibility of their web development projects for clients.