Fact sheet: Linked data
This is the first in a series of Fact Sheets we hope to post. The Fact Sheets will be short posts that offer a basic summary and a selection of useful resources on a given topic.
The Fact Sheets will cover topics that are emerging trends in the library and information sector and/or topics that have already been covered by other library/information professions. We hope the Fact Sheets will be a starting block for someone who is interested in the topic.
We will try to maintain the resources section for each Fact Sheet as the topics evolve and when one of you becomes an expert in the topic, we hope you want to present at one of our events!
Please add your own comments, suggestions and resources in the comments box.
Definition – The short answer – it’s about linking data sets. Linked data will enable us to link related data or documents together.
Background: If you searched NLPN on Google you would get our Twitter page, blog and events pages as well as results about Nonlinear Phase Noise or the National Literacy Programme in Namibia. It would be hard to remove all of the different variations of the NLPN you didn’t want from the search engine results because you would already have to know what you wanted to remove and this is not always possible. Also search engines are not designed for complex searches; complex searches belong to specialist databases.
The acronym ‘NLPN’ means different things to different people and context is key. Just by reading this blog, you would know that when I refer to the NLPN, the network or an event, my use of the word/phrase is loaded with meaning – I’m referring to the New Library Professionals Network and its activities. This is because the spoken word is loaded with meaning and context, which computers cannot understand. Linked data will go some way towards achieving context in digital systems as each name will have a URI (a Uniform Resource Identifier) record which contains information that makes that name unique. For instance, the metadata (which would be created/stored on the content management system of the website that was publishing the information, for example) would contain fields that identify NLPN as an acronym of the New Library Professionals Network, formerly Manchester NLPN etc. along with links to the URIs for each of the co-founders, which would then link to the URI records about the Universities they studied at or their place of work. Thus creating a web of linked information.
In order to create uniformity and avoid discrepancies in URI records, Berners-Lee (Bizer 2009) suggests that we should be able to look up URI records on the web (using HTTP) so that if you wanted to mention NLPN in an online article, you would be able to discover the record and link to the correct URI and not the URI on Nonlinear Phase Noise. The idea of one universal standard for creating a URI record is important, although some organisations have created their own set of records because they are only interested in linking to their own data within a closed system. The BBC is one example; they have created their own ontologies because they are only linking to data they have created in order to make full use of their own published content.
But doesn’t hyperlinking do the same job? No, whilst we have become good at hyperlinking words to different content there is no meaning behind it and it does not express the relationship between the word and the new site. By hyperlinking the name NLPN to our blog suggests that the blog is the NLPN, which it isn’t. The blog is one aspect or connection of the network the same way Twitter or Facebook is another aspect. Combined they are parts that go towards the sum total.
The impact: For organisations linked data, as the BBC has demonstrated, will enable them to link data and products that they have published, they will also be able to gather information and analyse this data to discover connections within the content. As a user, information would be more accessible and tailored to your search needs.
Summary: Linked data will enable us to classify information, creating clear links and expressing relationships between pieces of information that are interconnected.
The key article – Bizer, C., Health, T and Berners-Lee, T. (2009) Linked Data – The Story So Far in The International Journal of Semantic Web and Information Systems
Bauer, F and Kaltenbock, M. Linked Open Data: The Essentials (accessed 11.04.2016)
BBC (2014) Linked Data: new ontologies website (accessed 11.04.2016)
Data.Gov.uk. Sir Tim Berners-Lee’s talk from TED2009 (accessed 11.04.2016)
De Keyzer, M (2013) Understanding Linked Data by example. SEMIC – Semantic Interoperability Community
Sporny, M. What is Linked Data (YouTube clip – accessed 03.08.2016)
W3C (2015) Linked Data (accessed 11.04.2016)
This is not an exhaustive list, but a sample of a few articles or links which we have read and found useful. Please feel free to add your own suggestions in the comments box below.
Want to know more about Linked Data? Slides are available from the free UKSG webinar here