Extensible Markup Language (XML) is a flexible text format used to store and transport data. It allows users to define their own tags, making it easy to create structured documents that can be read by both humans and machines. XML is widely used in web services, data interchange, and configuration files. One of the key features of XML is its ability to separate data from presentation. This means that the same XML data can be displayed in different ways depending on the application or user needs. XML is also platform-independent, making it a popular choice for data sharing across different systems.