A microformat (sometimes abbreviated Î¼F) is a web-based approach to semantic markup which seeks to re-use existing HTML/XHTML tags to convey metadata and other attributes in web pages and other contexts that support (X)HTML such as RSS. This approach allows software to process information intended for end-users (such as contact information, geographic coordinates, calendar events, and similar information) automatically.
Although the content of web pages is technically already capable of “automated processing”, and has been since the inception of the web, such processing is difficult because the traditional markup tags used to display information on the web do not describe what the information means. Microformats can bridge this gap by attaching semantics, and thereby obviate other, more complicated, methods of automated processing, such as natural language processing or screen scraping. The use, adoption and processing of microformats enables data items to be indexed, searched for, saved or cross-referenced, so that information can be reused or combined.
As of 2010, microformats allow the encoding and extraction of events, contact information, social relationships and so on. Established microformats such as hCard are published on the web more than alternatives like schema (microdata) and RDFa.
XHTML and HTML standards allow for the embedding and encoding of semantics within the attributes of markup tags. Microformats take advantage of these standards by indicating the presence of metadata using the following attributes:
classClassnamerelrelationship, description of the target address in an anchor-element (<a href=… rel=…>…</a>)revreverse relationship, description of the referenced document (in one case, otherwise deprecated in microformats)For example, in the text “The birds roosted at 52.48, -1.89” is a pair of numbers which may be understood, from their context, to be a set of geographic coordinates. With wrapping inspans (or other HTML elements) with specific class names (in this case geo, latitude and longitude, all part of the geo microformat specification):
The birds roosted at
software agents can recognize exactly what each value represents and can then perform a variety of tasks such as indexing, locating it on a map and exporting it to a GPS device.