XML is a data transmission standard, also known as: eXtensible Markup Language.
The XML documentation is managed by World Wide Web Consortium (W3C), and was last updated in 2008.
XML (eXtensible Markup Language) is a markup language for storing and transporting data. Unlike HTML, which uses a fixed set of tags to display content, XML uses a flexible, user-defined structure to describe the data itself. This makes it a self-describing language.
The core purpose of XML is to make data readable by both humans and machines, promoting interoperability between different systems.
It relies on a tree-like structure of elements and attributes. For example, a document might have a <book> element containing <title>, <author>, and <price> elements:
<book>
<title>War of the Worlds</title>
<author>HG Wells</author>
<price>£15</price
</book>
Strengths
- Self-describing - completely flexible
- Hierarchical structure
- Can be used for real-time data transfers (although less often these days)
Limitations
- For interoperability, a Document Type Definition is required. It sets the rules for how a particular XML file should be structured
- Can be cumbersome for developers to work with
- Quite bulky and verbose