Data Formats Part 6 Extensible Markup Language (XML)

What is Extensible Markup Language (XML)?

A text-based format designed to store and transmit data in a way that is both human-readable and machine-readable.

XML tells a system what the data is.

What are the characteristics of XML?

User-Defined Tags

Hierarchical Structure

Strict Rules

Metadata via Attributes

What are User-Defined Tags?

You can invent tags that make sense for your data, such as , , or .

Rather than HTML, which has fixed sets of tags like

, or

What is a Hierarchical structure?

XML uses a "tree" structure where data is nested. Every file has one "root" element that contains all other elements.

What are Strict Rules?

XML is very disciplined.

Every opening tag (e.g., ) must have a corresponding closing tag (), and tags must be nested correctly.

What is Metadata via Attributes?

You can add extra information to a tag using attributes

E.G. .

What are the uses of XML?

1. Microsoft Office and OpenOffice Documents - Every time you save a .docx, .xlsx, or .pptx file, you are actually creating a bundle of XML files.

2. Sitemaps for Search Engines (SEO)

3. Standardised Industry Data

4. Configuration for Enterprise Software

5. RSS (Really Simple Syndication) Feeds and Podcasts

6. Vector Graphics (SVG)

What are the advantages of XML?

- XML is a flexible and highly customisable format

What are the disadvantages of XML?

-Verbose

(Much larger file sizes with redundant data, reducing the efficiency of transport and file size)