XML, or eXtensible Markup Language, is a versatile markup language designed to store and transport data. It is both human-readable and machine-readable, making it a popular choice for data interchange between systems. XML allows users to define their own tags, providing flexibility in how data is structured and represented. 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 context. XML is widely used in various applications, including web services, configuration files, and document storage.