SIOC Core Ontology Namespace
type: Ontology
type: Thing
version info: Revision: 1.35
description: SIOC (Semantically-Interlinked Online Communities) is an ontology for describing the information in online communities. This information can be used to export information from online communities and to link them together. The scope of the application areas that SIOC can be used for includes (and is not limited to) weblogs, message boards, mailing lists and chat channels.

SIOC Core Ontology Specification

Community
type: Class
comment: Community is a high-level concept that defines an online community and what it consists of.
disjoint with: Item
disjoint with: Role
disjoint with: User Account

Container
type: Class
comment: An area in which content Items are contained.
disjoint with: Item
disjoint with: Role
disjoint with: User Account
disjoint with: Usergroup

Forum
type: Class
comment: A discussion area on which Posts or entries are made.
subclass of: Container

Item
type: Class
comment: An Item is something which can be in a Container.
disjoint with: Container
disjoint with: Role
disjoint with: Space
disjoint with: User Account
disjoint with: Usergroup

Post
type: Class
comment: An article or message that can be posted to a Forum.
subclass of: Item
subclass of: Document

Role
type: Class
comment: A Role is a function of a UserAccount within a scope of a particular Forum, Site, etc.
disjoint with: Container
disjoint with: Item
disjoint with: Space
disjoint with: User Account
disjoint with: Usergroup

Space
type: Class
comment: A Space is a place where data resides, e.g. on a website, desktop, fileshare, etc.
disjoint with: Item
disjoint with: Role
disjoint with: User Account
disjoint with: Usergroup

Site
type: Class
comment: A Site can be the location of an online community or set of communities, with UserAccounts and Usergroups creating Items in a set of Containers. It can be thought of as a web-accessible data Space.
subclass of: Space

Thread
type: Class
comment: A container for a series of threaded discussion Posts or Items.
subclass of: Container

User Account
type: Class
comment: A user account in an online community site.
subclass of: OnlineAccount
disjoint with: Container
disjoint with: Item
disjoint with: Role
disjoint with: Space
disjoint with: Usergroup

Usergroup
type: Class
comment: A set of UserAccounts whose owners have a common purpose or interest. Can be used for access control purposes.
disjoint with: Container
disjoint with: Item
disjoint with: Role
disjoint with: Space
disjoint with: User Account

about
type: ObjectProperty
comment: Specifies that this Item is about a particular resource, e.g. a Post describing a book, hotel, etc.
domain: Item

account of
type: ObjectProperty
comment: Refers to the foaf:Agent or foaf:Person who owns this sioc:UserAccount.
domain: User Account
range: Agent
inverse of: account

addressed to
type: ObjectProperty
comment: Refers to who (e.g. a UserAccount, e-mail address, etc.) a particular Item is addressed to.
domain: Item

administrator of
type: ObjectProperty
inverse of: has administrator
comment: A Site that the UserAccount is an administrator of.
domain: User Account
range: Site

attachment
type: ObjectProperty
comment: The URI of a file attached to an Item.
domain: Item

avatar
type: ObjectProperty
comment: An image or depiction used to represent this UserAccount.
domain: User Account
sub property of: depiction

container of
type: ObjectProperty
inverse of: has container
comment: An Item that this Container contains.
domain: Container
range: Item

content
type: DatatypeProperty
comment: The content of the Item in plain text format.
domain: Item
range: Literal

creator of
type: ObjectProperty
inverse of: has creator
comment: A resource that the UserAccount is a creator of.
domain: User Account

earlier version
type: TransitiveProperty
comment: Links to a previous (older) revision of this Item or Post.
domain: Item
range: Item
inverse of: later version

email
type: ObjectProperty
comment: An electronic mail address of the UserAccount.
domain: User Account

email sha1
type: DatatypeProperty
comment: An electronic mail address of the UserAccount, encoded using SHA1.
domain: User Account
range: Literal

embeds knowledge
type: ObjectProperty
comment: This links Items to embedded statements, facts and structured content.
domain: Item
range: Graph

feed
type: ObjectProperty
comment: A feed (e.g. RSS, Atom, etc.) pertaining to this resource (e.g. for a Forum, Site, UserAccount, etc.).

follows
type: ObjectProperty
comment: Indicates that one UserAccount follows another UserAccount (e.g. for microblog posts or other content item updates).
domain: User Account
range: User Account

function of
type: ObjectProperty
inverse of: has function
comment: A UserAccount that has this Role.
domain: Role

has administrator
type: ObjectProperty
inverse of: administrator of
comment: A UserAccount that is an administrator of this Site.
domain: Site
range: User Account

has container
type: ObjectProperty
inverse of: container of
comment: The Container to which this Item belongs.
domain: Item
range: Container

has creator
type: ObjectProperty
inverse of: creator of
comment: This is the UserAccount that made this resource.
range: User Account

has discussion
type: ObjectProperty
comment: The discussion that is related to this Item.
domain: Item

has function
type: ObjectProperty
inverse of: function of
comment: A Role that this UserAccount has.
range: Role

has host
type: ObjectProperty
inverse of: host of
comment: The Site that hosts this Forum.
domain: Forum
range: Site

has member
type: ObjectProperty
inverse of: member of
comment: A UserAccount that is a member of this Usergroup.
domain: Usergroup
range: User Account

has moderator
type: ObjectProperty
comment: A UserAccount that is a moderator of this Forum.
domain: Forum
range: User Account

has modifier
type: ObjectProperty
inverse of: modifier of
comment: A UserAccount that modified this Item.
domain: Item
range: User Account

has owner
type: ObjectProperty
inverse of: owner of
comment: A UserAccount that this resource is owned by.
range: User Account

has parent
type: ObjectProperty
inverse of: parent of
comment: A Container or Forum that this Container or Forum is a child of.
domain: Container
range: Container

has reply
type: ObjectProperty
inverse of: reply of
sub property of: related to
comment: Points to an Item or Post that is a reply or response to this Item or Post.
domain: Item
range: Item

has scope
type: ObjectProperty
inverse of: scope of
comment: A resource that this Role applies to.
domain: Role

has space
type: ObjectProperty
inverse of: space of
comment: A data Space which this resource is a part of.
range: Space

has subscriber
type: ObjectProperty
inverse of: subscriber of
comment: A UserAccount that is subscribed to this Container.
domain: Container
range: User Account

has usergroup
type: ObjectProperty
inverse of: usergroup of
comment: Points to a Usergroup that has certain access to this Space.
domain: Space
range: Usergroup

host of
type: ObjectProperty
inverse of: has host
comment: A Forum that is hosted on this Site.
domain: Site
range: Forum

id
type: DatatypeProperty
comment: An identifier of a SIOC concept instance. For example, a user ID. Must be unique for instances of each type of SIOC concept within the same site.
range: Literal

ip address
type: DatatypeProperty
comment: The IP address used when creating this Item. This can be associated with a creator. Some wiki articles list the IP addresses for the creator or modifiers when the usernames are absent.
domain: Item
range: Literal

last activity date
type: DatatypeProperty
comment: The date and time of the last activity associated with a SIOC concept instance, and expressed in ISO 8601 format. This could be due to a reply Post or Comment, a modification to an Item, etc.
range: Literal
sub property of: date

last item date
type: DatatypeProperty
comment: The date and time of the last Post (or Item) in a Forum (or a Container), in ISO 8601 format.
domain: Container
range: Literal
sub property of: date

last reply date
type: DatatypeProperty
comment: The date and time of the last reply Post or Comment, which could be associated with a starter Item or Post or with a Thread, and expressed in ISO 8601 format.
range: Literal
sub property of: date

later version
type: TransitiveProperty
comment: Links to a later (newer) revision of this Item or Post.
domain: Item
range: Item
inverse of: earlier version

latest version
type: ObjectProperty
comment: Links to the latest revision of this Item or Post.
domain: Item
range: Item

link
type: ObjectProperty
comment: A URI of a document which contains this SIOC object.

links to
type: ObjectProperty
comment: Links extracted from hyperlinks within a SIOC concept, e.g. Post or Site.
sub property of: references

member of
type: ObjectProperty
inverse of: has member
comment: A Usergroup that this UserAccount is a member of.
domain: User Account
range: Usergroup

moderator of
type: ObjectProperty
inverse of: has moderator
comment: A Forum that a UserAccount is a moderator of.
domain: User Account
range: Forum

modifier of
type: ObjectProperty
inverse of: has modifier
comment: An Item that this UserAccount has modified.
domain: User Account
range: Item

name
type: DatatypeProperty
comment: The name of a SIOC concept instance, e.g. a username for a UserAccount, group name for a Usergroup, etc.
range: Literal

next by date
type: ObjectProperty
inverse of: previous by date
comment: Next Item or Post in a given Container sorted by date.
domain: Item
range: Item

next version
type: ObjectProperty
inverse of: previous version
comment: Links to the next revision of this Item or Post.
domain: Item
range: Item
sub property of: later version

note
type: DatatypeProperty
comment: A note associated with this resource, for example, if it has been edited by a UserAccount.
range: Literal

num authors
type: DatatypeProperty
comment: The number of unique authors (UserAccounts and unregistered posters) who have contributed to this Item, Thread, Post, etc.
range: nonNegativeInteger

num items
type: DatatypeProperty
comment: The number of Posts (or Items) in a Forum (or a Container).
domain: Container
range: nonNegativeInteger

num replies
type: DatatypeProperty
comment: The number of replies that this Item, Thread, Post, etc. has. Useful for when the reply structure is absent.
range: nonNegativeInteger

num threads
type: DatatypeProperty
comment: The number of Threads (AKA discussion topics) in a Forum.
domain: Forum
range: nonNegativeInteger

num views
type: DatatypeProperty
comment: The number of times this Item, Thread, UserAccount profile, etc. has been viewed.
range: nonNegativeInteger

owner of
type: ObjectProperty
inverse of: has owner
comment: A resource owned by a particular UserAccount, for example, a weblog or image gallery.
domain: User Account

parent of
type: ObjectProperty
inverse of: has parent
comment: A child Container or Forum that this Container or Forum is a parent of.
domain: Container
range: Container

previous by date
type: ObjectProperty
inverse of: next by date
comment: Previous Item or Post in a given Container sorted by date.
domain: Item
range: Item

previous version
type: ObjectProperty
inverse of: next version
comment: Links to the previous revision of this Item or Post.
domain: Item
range: Item
sub property of: earlier version

related to
type: ObjectProperty
comment: Related Posts for this Post, perhaps determined implicitly from topics or references.

reply of
type: ObjectProperty
inverse of: has reply
sub property of: related to
comment: Links to an Item or Post which this Item or Post is a reply to.
domain: Item
range: Item

scope of
type: ObjectProperty
inverse of: has scope
comment: A Role that has a scope of this resource.
range: Role

sibling
type: SymmetricProperty
comment: An Item may have a sibling or a twin that exists in a different Container, but the siblings may differ in some small way (for example, language, category, etc.). The sibling of this Item should be self-describing (that is, it should contain all available information).
domain: Item
range: Item

space of
type: ObjectProperty
inverse of: has space
comment: A resource which belongs to this data Space.
domain: Space

subscriber of
type: ObjectProperty
inverse of: has subscriber
comment: A Container that a UserAccount is subscribed to.
domain: User Account
range: Container

topic
type: ObjectProperty
comment: A topic of interest, linking to the appropriate URI, e.g. in the Open Directory Project or of a SKOS category.
sub property of: subject

usergroup of
type: ObjectProperty
inverse of: has usergroup
comment: A Space that the Usergroup has access to.
domain: Usergroup
range: Space

User
type: DeprecatedClass
comment: UserAccount is now preferred. This is a deprecated class for a User in an online community site.
equivalent class: User Account
subclass of: OnlineAccount
disjoint with: Container
disjoint with: Item
disjoint with: Role
disjoint with: Space
disjoint with: Usergroup
version info: This class is deprecated. Use sioc:UserAccount from the SIOC ontology instead.

title
type: DeprecatedProperty
type: DatatypeProperty
comment: This is the title (subject line) of the Post. Note that for a Post within a threaded discussion that has no parents, it would detail the topic thread.
domain: Post
range: Literal
version info: This property is deprecated. Use dcterms:title from the Dublin Core ontology instead.

content encoded
type: DeprecatedProperty
type: DatatypeProperty
comment: The encoded content of the Post, contained in CDATA areas.
domain: Post
range: Literal
version info: This property is deprecated. Use content:encoded from the RSS 1.0 content module instead.

created at
type: DeprecatedProperty
type: DatatypeProperty
comment: When this was created, in ISO 8601 format.
domain: Post
range: Literal
version info: This property is deprecated. Use dcterms:created from the Dublin Core ontology instead.

description
type: DeprecatedProperty
type: DatatypeProperty
comment: The content of the Post.
domain: Post
range: Literal
version info: This property is deprecated. Use sioc:content or other methods (AtomOwl, content:encoded from RSS 1.0, etc.) instead.

first name
type: DeprecatedProperty
type: DatatypeProperty
comment: First (real) name of this User. Synonyms include given name or christian name.
domain: User Account
range: Literal
version info: This property is deprecated. Use foaf:name or foaf:firstName from the FOAF vocabulary instead.

group of
type: DeprecatedProperty
type: ObjectProperty
inverse of: has group
version info: This property has been renamed. Use sioc:usergroup_of instead.

has group
type: DeprecatedProperty
type: ObjectProperty
inverse of: group of
version info: This property has been renamed. Use sioc:has_usergroup instead.

has part
type: DeprecatedProperty
type: ObjectProperty
inverse of: part of
comment: An resource that is a part of this subject.
version info: This property is deprecated. Use dcterms:hasPart from the Dublin Core ontology instead.

last name
type: DeprecatedProperty
type: DatatypeProperty
comment: Last (real) name of this user. Synonyms include surname or family name.
domain: User Account
range: Literal
version info: This property is deprecated. Use foaf:name or foaf:surname from the FOAF vocabulary instead.

modified at
type: DeprecatedProperty
type: DatatypeProperty
comment: When this was modified, in ISO 8601 format.
domain: Post
range: Literal
version info: This property is deprecated. Use dcterms:modified from the Dublin Core ontology instead.

part of
type: DeprecatedProperty
type: ObjectProperty
inverse of: has part
comment: A resource that the subject is a part of.
version info: This property is deprecated. Use dcterms:isPartOf from the Dublin Core ontology instead.

reference
type: DeprecatedProperty
type: ObjectProperty
comment: Links either created explicitly or extracted implicitly on the HTML level from the Post.
domain: Post
version info: Renamed to sioc:links_to.

subject
type: DeprecatedProperty
type: DatatypeProperty
comment: Keyword(s) describing subject of the Post.
domain: Post
range: Literal
version info: This property is deprecated. Use dcterms:subject from the Dublin Core ontology for text keywords and sioc:topic if the subject can be represented by a URI instead.