demiblog.org:
Metadata Profile

Documents may use the HTML <link> element to link to secondary metadata profiles using the rules described in RFC 2731. This is used to provide namespacing in HTML metadata, and to circumvent the limitation of the HTML "profile" attribute whereby it may only take one profile URL.

tag

Indicates that the referred resource serves as a "tag", or keyword/subject, for the referring page.

license

Indicates that the referred resource is a licence for the referring page.

contact

Someone you know how to get in touch with. Often symmetric.

acquaintance

Someone who you have exchanged greetings and not much (if any) more — maybe a short conversation or two. Often symmetric.

friend

Someone you are a friend to. A compatriot, buddy, home(boy|girl) that you know. Often symmetric.

met

Someone who you have actually met in person. Symmetric.

co-worker

Someone a person works with, or works at the same organization as. Symmetric. Usually transitive.

colleague

Someone in the same field of study/activity. Symmetric. Often transitive.

co-resident

Someone you share a street address with. Symmetric and transitive.

neighbor

Someone who lives nearby, perhaps only at an adjacent street address or doorway. Symmetric. Often transitive.

child

A person's genetic offspring, or someone that a person has adopted and takes care of. Inverse is parent.

parent

Inverse of child.

sibling

Someone a person shares a parent with. Symmetric. Usually transitive.

spouse

Someone you are married to. Symmetric. Not transitive.

kin

A relative, someone you consider part of your extended family. Symmetric and typically transitive.

muse

Someone who brings you inspiration. No inverse.

crush

Someone you have a crush on. No inverse.

date

Someone you are dating. Symmetric. Not transitive.

sweetheart

Someone with whom you are intimate and at least somewhat committed, typically exclusively. Symmetric. Not transitive.

me

A link to yourself at a different URL. Exclusive of all other XFN values. Required symmetric. There is an implicit "me" relation from a subdirectory to all of its contents.

vcalendar

A container for one or more events (vevent). This property is optional; if there is only one event then omit it

vevent

A container for one event

dtstart

Date/time of the start of the event

dtend

Date/time of the end of the event

duration

Length of the event

summary

Short synopsis of the event, or the title of the event, or the name of the event

uid

A globally unique identifier for the event; typically a URL is used

dtstamp

Date/time of when the document containing information about the event was created

method

Values for this property are: PUBLISH, REQUEST, REPLY, ADD, CANCEL, REFRESH, COUNTER, or DECLINECOUNTER. For example, a value of REQUEST indicates that a request is being made for the event to occur

category

Common values are: MEETING, APPOINTMENT, CONFERENCE, EXPO. Note: this property may be repeated (an event may belong in several categories)

location

Tells where the event is to be held

url

A URL to a page that contains the definitive/preferred information about an event; uid and url are typically the same

description

A more detailed synopsis of the event than that provided by summary

last-modified

Date/time the information about the event was updated

status

Values are: TENTATIVE, CONFIRMED, CANCELLED

class

Access classification of the event information; values are: PUBLIC, PRIVATE, CONFIDENTIAL

vcard

A container for the rest of the class names defined in this XMDP profile. See section 1. of RFC 2426.

fn

See section 3.1.1 of RFC 2426.

n

See section 3.1.2 of RFC 2426. May be inferred per Implied "N" Optimization.

family-name

See "Family Name" in section 3.1.2 of RFC 2426.

given-name

See "Given Name" in section 3.1.2 of RFC 2426.

additional-name

See "Additional Names" in section 3.1.2 of RFC 2426.

honorific-prefix

See "Honorific Prefixes" in section 3.1.2 of RFC 2426.

honorific-suffix

See "Honorific Suffixes" in section 3.1.2 of RFC 2426.

nickname

See section 3.1.3 of RFC 2426.

photo

See section 3.1.4 of RFC 2426. Typically used with an <img> tag. Use the 'src' attribute for URI values. Use the 'data:' URI scheme for binary values.

bday

See section 3.1.5 of RFC 2426. Typically used with an <abbr> tag with the 'title' attribute for the date value, and a human readable date inside the element.

adr

See section 3.2.1 of RFC 2426.

post-office-box

See "post office box" in section 3.2.1 of RFC 2426.

extended-address

See "extended address" in section 3.2.1 of RFC 2426.

street-address

See "street address" in section 3.2.1 of RFC 2426.

locality

See "locality" in section 3.2.1 of RFC 2426.

region

See "region" in section 3.2.1 of RFC 2426.

postal-code

See "postal code" in section 3.2.1 of RFC 2426.

country-name

See "country name" in section 3.2.1 of RFC 2426.

type

See "type" in the various sections of RFC 2426.

value

This class name is used to distinguish the actual value of a property from any other cruft that may be in the element representing the property.

label

See section 3.2.2 of RFC 2426.

tel

See section 3.3.1 of RFC 2426.

email

See section 3.3.2 of RFC 2426.

mailer

See section 3.3.3 of RFC 2426.

tz

See section 3.4.1 of RFC 2426. Typically used with an <abbr> tag with the 'title' attribute for the tz value, and a human readable time zone inside the element.

geo

See section 3.4.2 of RFC 2426.

latitude

See "latitude" in section 3.4.2 of RFC 2426.

longitude

See "longitude" in section 3.4.2 of RFC 2426.

title

See section 3.5.1 of RFC 2426.

role

See section 3.5.2 of RFC 2426.

logo

See section 3.5.3 of RFC 2426. Typically used with an <img> tag. Use the 'src' attribute for URI values. Use the 'data:' URI scheme for binary values.

agent

See section 3.5.4 of RFC 2426. If the value is a vCard, then use a nest hCard. For simplicity in that case, the same element that has the class name of "agent" should use the class name of "vcard".

org

See section 3.5.5 of RFC 2426.

organization-name

See "Organization Name" in section 3.5.5 of RFC 2426. May be inferred per Implied "organization-name" Optimization.

organization-unit

See "Organization Unit" in section 3.5.5 of RFC 2426.

category

See section 3.6.1 of RFC 2426.

note

See section 3.6.2 of RFC 2426.

rev

See section 3.6.4 of RFC 2426. Typically used with an <abbr> tag with the 'title' attribute for the date value, and a human readable date inside the element.

sort-string

See section 3.6.5 of RFC 2426.

sound

See section 3.6.6 of RFC 2426. Typically used with either an <a> or <object> tag. Use the 'data:' URI scheme for binary values.

uid

See section 3.6.7 of RFC 2426.

url

See section 3.6.8 of RFC 2426. Typically used with an <a> tag.

class

See section 3.7.1 of RFC 2426.

key

See section 3.7.2 of RFC 2426. Typically used with an <abbr> tag with the 'title' attribute for the key value, and a human readable key equivalent inside the element.