Microformats are simple, open standards that use existing HTML/XHTML tags to add semantic meaning to published content. They allow both humans and machines to easily find and understand relationships, people, events and other common types of information published on the web. Examples of microformats include hCard for contact information, hCalendar for events, and XFN for social relationships. Microformats aim to make semantically tagged information available on the web in a simple way without requiring extensive technical knowledge.