Microformat

From Wikipedia, the free encyclopedia


In web development, a microformat (sometimes abbreviated μF or uF) is a way of adding simple semantic meaning to human-readable content which is otherwise, from a machine's point of view, just plain text. They allow data items such as events, contact details or locations, on HTML (or XHTML) web pages, to be meaningfully detected and the information in them to be extracted by software, and indexed, searched for, saved or cross-referenced, so that it can be reused or combined.

More technically, they are items of semantic mark up, using just standard (X)HTML with a set of common class-names. They are open and available, freely, for anyone to use.

Current microformats allow the encoding and extraction of events, contact information, social relationships, and so on. More are being developed. Version 3 of the Firefox browser, as well as version 8 of Internet Explorer are expected to include native support for microformats.



Principles

(X)HTML standards allow for semantics to be embedded and encoded within them. This is done using specific HTML attributes:

class
rel
rev
For example, 52.48,-1.89 is a pair of numbers which may be understood, from their context, to be a set of geographic coordinates. By wrapping them in spans (or other HTML elements) with specific class names (in this case part of the geo microformat specification):

<span class="geo"><span class="latitude">52.48</span>, <span class="longitude">-1.89</span></span>

machines can be told exactly what each value represents, and can then index it, look it up on a map, export it to a GPS device, etc.


Uses of microformats
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Using microformats within HTML code provides additional formatting and semantic data that can be used by applications. These could be applications that collect data about on-line resources, such as web crawlers, or desktop applications such as e-mail clients or scheduling software.

Several browser extensions, such as Operator, provide the ability to detect microformats within an HTML document and export them into formats compatible with contact management and calendar utilities, such as Microsoft Outlook.

Microsoft expressed a desire to incorporate Microformats into upcoming projects; as have other software companies.

In Wikipedia - and more generally in MediaWiki - microformats are used as part of templates like {{coord}} for example.

Creation of microformats
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Most of the existing microformats were created at the microformat wiki and associated mailing list, by a process of gathering examples of web publishing behaviour, then codifying it. Some other microformats (such as rel=nofollow and unAPI have been proposed, or developed, elsewhere.