Microformat
Microformats are a markup format for semantic annotation of HTML or XHTML. Microformat annotations can be easily extracted from Web pages and make other programs (such as search engines ) the meaning of the page content understandable.
Each microformat is designed for a specific topic or area of knowledge. So there are microformats for appointments, for contact information and for social relationships.
Example
The previously existing (X) HTML standards allow minimal semantic annotations using the following attributes:
Contact information is usually represented in HTML as simple elements:
So it is a software, such as Browser plugins or search engine possible to read the information and to transfer them to other applications such as address books or directions.
Dissemination
To spread was founded by Dan Cederholm with Tantek Çelik on 20 June 2005, the project microformats.org. The impetus was the company Technorati, which is concerned with the technology of search engines and the search engine kitchen.technorati.com for microformats operates.
For different browser such as Firefox, Chrome, Internet Explorer and Safari plugins exist can evaluate the individual micro formats.
A common microformat is nofollow.
Alternatives
RDFa is a similar approach, in which RDF ( consisting of the well-known Semantic Web Resource Description Framework for the annotation of any resource ) is embedded in (X ) HTML. To this end, however, the (X) HTML syntax has been slightly expanded. RDFa is a little harder to write than microformats, but more expressive, since it is not limited to specific subject areas, but can be described by means of suitable ontologies things from all areas.