# XML Information Card
Who / What
Extensible Markup Language (XML) is a markup language and file format designed for storing, transmitting, and reconstructing data in a structured, human-readable, and machine-interpretable manner. It defines rules for encoding documents with customizable tags to represent various types of information, making it versatile for applications across industries.
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Background & History
Developed as part of the broader effort to standardize web data exchange, XML was introduced in 1998 by the **World Wide Web Consortium (W3C)**. It emerged from earlier markup languages like SGML and HTML, addressing limitations such as rigidity and lack of flexibility for customizable data structures. Key milestones include its formal standardization in the W3C’s *XML 1.0 Specification* (1998) and subsequent expansions like XML Schema (XSD), XPath, and XSLT, which expanded its functionality for validation, querying, and transformation.
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Why Notable
XML remains foundational for data interoperability on the internet due to its simplicity, extensibility, and neutrality. It enables seamless integration between diverse systems by allowing standardized tagging of information, supporting applications like e-commerce (e.g., EDI), healthcare records (HL7), and web services (SOAP). Its adaptability ensures relevance across evolving digital landscapes, from legacy systems to modern cloud-based architectures.
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In the News
While not a news-driven entity, XML’s enduring importance is highlighted by its continued adoption in emerging technologies like **IoT data protocols** and **blockchain interoperability**. Recent developments include its integration with **JSON-LD** for hybrid data formats and support in APIs (e.g., RESTful services), underscoring its role as a backbone for structured data exchange.
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Key Facts
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