An ontology formally represents knowledge as concepts and relationships within a domain. It defines classes and subclasses of concepts, as well as properties and instances of classes. An ontology uses a structured format like RDF triples to define these components and can be used to model and reason about a domain. Popular ontology languages include RDF, RDFS, and OWL, which allow linking open data from different sources using common identifiers.

1. COMMIT/ E-FOODLAB
Don Willems
don.willems@wur.nl / @oekalegon
What is an Ontology?

2. COMMIT/ E-FOODLAB
In computer science and information science, an ontology
formally represents knowledge as a set of concepts within a
domain, and the relationships between pairs of concepts. It can be
used to model a domain and support reasoning about concepts.
Source: http://en.wikipedia.org/wiki/Ontology_(information_science)

3. COMMIT/ E-FOODLAB
In computer science and information science, an ontology
formally represents knowledge as a set of concepts within a
domain, and the relationships between pairs of concepts. It can be
used to model a domain and support reasoning about concepts.
Source: http://en.wikipedia.org/wiki/Ontology_(information_science)
computer science
information science
ontology
knowledge
set of concepts
concepts
domain
relationships reasoning
subject ofsubject of
representation
of
contains
contains
contains
contains
description of
makes
use of
supports

4. COMMIT/ E-FOODLAB
Components of an Ontology
Classes
(concepts, types, universals)
Apple

5. COMMIT/ E-FOODLAB
Components of an Ontology
Classes
(concepts, types, universals)
Apple
Pome
sub class of
Fruit
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of

6. COMMIT/ E-FOODLAB
Components of an Ontology
Instances
(individuals, particulars)
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of

7. COMMIT/ E-FOODLAB
Components of an Ontology
Instances
(individuals, particulars)
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of

8. COMMIT/ E-FOODLAB
Components of an Ontology
Instances
(individuals, particulars)
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of
The apple in
my lunch box
type
The apple on
the tree
in my garden
type

9. COMMIT/ E-FOODLAB
Components of an Ontology
Relations
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of
The apple in
my lunch box
type
The apple on
the tree
in my garden
type

10. COMMIT/ E-FOODLAB
Components of an Ontology
Relations
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of
The apple in
my lunch box
type
The apple on
the tree
in my garden
type

11. COMMIT/ E-FOODLAB
Components of an Ontology
Relations
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of
The apple in
my lunch box
type
The apple on
the tree
in my garden
type

12. COMMIT/ E-FOODLAB
Components of an Ontology
Relations
Apple
Pome
Fruit
sub class of
sub class of
Pear
sub class of
Elstar Golden
Delicious
sub class of
sub class of
The apple in
my lunch box
type
The apple on
the tree
in my garden
type

13. COMMIT/ E-FOODLAB
Components of an Ontology
Relations
Apple
Pome
sub class of
sub class of
Pear
sub class
Elstar Golden
Delicious
sub cla
sub class of
The apple in
my lunch box
type
The apple o
the tree
in my garde
type

14. COMMIT/ E-FOODLAB
Components of an Ontology
Relations
Apple
Pome
sub class of
sub class of
Pear
sub class
Elstar Golden
Delicious
sub cla
sub class of
The apple in
my lunch box
type
The apple o
the tree
in my garde
type
has colour
red
location
my lunch box

15. COMMIT/ E-FOODLAB
Ontology Languages
Triples
The apple in
my lunch box
Apple
Pome
sub class of
sub class of
Pear
sub class
Elstar Golden
Delicious
sub cla
sub class of
type
The apple o
the tree
in my garde
type
has colour
red
location
my lunch box

16. COMMIT/ E-FOODLAB
Ontology Languages
Triples
The apple in
my lunch box
has colour red

17. COMMIT/ E-FOODLAB
Ontology Languages
Triples
The apple in
my lunch box
has colour red
SUBJECT PREDICATE OBJECT

18. COMMIT/ E-FOODLAB
Ontology Languages
Triples
SUBJECT PREDICATE OBJECT
Elstar sub class of Apple
Elstar label “Elstar”

19. COMMIT/ E-FOODLAB
Ontology Languages
Triples
SUBJECT PREDICATE OBJECT
Elstar sub class of Apple
Elstar label “Elstar”
Apple label “Apple”
Apple total production 69,569,612

20. COMMIT/ E-FOODLAB
Ontology Languages
RDF
(Resource Description Framework)
SUBJECT PREDICATE OBJECT
Elstar sub class of Apple
Elstar label “Elstar”
Apple label “Apple”
Apple total production 69,569,612
URI
(or blank node)
URI
URI
Literal
(number/string)
http://example.com/Elstar http://www.w3.org/2000/01/rdf-schema#subClassOf http://example.com/Apple
ex:Elstar rdfs:subClassOf ex:Apple

21. COMMIT/ E-FOODLAB
Vocabularies
RDF W3C Conceptual Description Method
RDFS W3C Basic elements for Ontologies
OWL W3C Ontologies
Dublin Core DCMI Metadata Discovery
AgroVoc FAO Food, Nutrition, Fisheries, Forestry, ...
Ontology of Measures FBR Units, Quantities, Scales, ...
Friend Of A Friend FOAF Biographic data, relations, ...
Gene Ontology GO consortium Gene and gene product attributes
Ontology of Astronomical Object
Types IVOA Astronomical object Types

22. COMMIT/ E-FOODLAB
Data
DBpedia
Data taken from info boxes in
Wikipedia
Geonames Geographical information
BBC Programmes TV Programmes, series, ...
DBLP Computer Science
Bibliography
Bibliographic metadata
DrugBank
Chemical, pharmacological and
pharmaceutical data
data.gov.uk Public data related to policy

23. COMMIT/ E-FOODLAB
Data
And Many More
PUBLIC DATA SETS
and
Not so public data sets

24. COMMIT/ E-FOODLAB
LINKED OPEN DATA
Remember URIs?

25. COMMIT/ E-FOODLAB
LINKED OPEN DATA
http://dbpedia.org/page/Nijmegen
Remember URIs?
http://www.w3.org/2002/07/owl#sameAs
http://sws.geonames.org/2750053/

26. COMMIT/ E-FOODLAB
LINKED OPEN DATA

27. COMMIT/ E-FOODLAB
World
Fact-
book
Pokedex
Pfam
Linked
LCCN
ChEMBL
SW
Dog
Food
AGROVOC
DBpedia
Tele-
graphis
dotAC
ERA
Open
Cyc
UB Mann-
heim
JISC
OS
totl.net
OAI
Portu-
guese
DBpedia
UMBEL
Affy-
metrix
riese
Open
o
ed
ta
UniProt
(Bio2RDF)
SSW
Thesau-
rus
Freebase
GEMET
P20
TCM
Gene
DIT
OMIM
Brainz
(DBTune)
LODE
SIDER
Project
Guten-
berg
ProDom
HGNC
Revyu
Gene
Ontology
URI
Burner
Eurécom
New
York
Times
ECS
South-
ampton
EPrints
LIBRIS
KEGG
Drug
VIVO
Cornell
WordNet
(RKB
Explorer)
Cornetto
DDC Deutsche
Bio-
graphie
Wiki
Ulm
BBC
Music
Drug
Bank
KIST
warql
Geo
Names
Pub
Chem
Good-
win
Family
flickr
wrappr
Thesau-
rus W
ked
Data
Linked
WordNet
(VUA)
Greek
DBpedia
GND
LinkedCT
SISVU
Didac-
talia
dbpedia
lite
BNB
LAAS
iServe
Geo
Species
VIVO UF
ntnu
lingvoj
PubMed
ACM
BBC
Wildlife
Finder
Calames
Chronic-
ling
America
data-
open-
ac-
uk
MARC
Codes
List
VIVO
Indiana
LCSH
bible
ontology
IdRef
Sudoc
KEGG
Enzyme
PRO-
SITE
Open
Calais
data
bnf.fr
lobid
Resources
IRIT
theses.
fr
Daily
Med
Taxo-
nomy
New-
castle
Poké-
pédia
BibBase
STITCH
PDB
.FM
sts
une)
YAGO
ECS
(RKB
Explorer)
Event
Media
my
Experi-
ment
m-
axon
ncept
KEGG
(DBtune)
Alpine
Ski
Austria
DBLP
(RKB
Explorer)
DBLP
(L3S)
RDF Book
Mashup
Uberblic
data
dcs
Last.FM
(rdfize)
RAE2001
Disea-
some
PSH
WordNet
(W3C)
semantic
web.org
SGD
UniProt
PBAC
UN/
LOCODE
Lexvo
Linked
MDB
Sudoc
ECS
South-
ampton
ePrints
Classical
(DB
Tune)
DBLP
(FU
Berlin)
Fishes
of
Texas
gnoss
Enipedia
ndlna
Budapest
CiteSeer

28. COMMIT/ E-FOODLAB
Thank you!
don.willems@wur.nl / @oekalegon