Overview#Linked Data is about using Web Linking to connect related data that wasn't previously linked, or using the Web to lower the barriers to linking data currently linked using other methods.
Wikipedia defines Linked Data as "a term used to describe a recommended best practice for exposing, sharing, and connecting pieces of data, information, and knowledge on the Semantic WEB using URIs and RDF."
Linked Data coined by Tim Berners-Lee, the inventor of the World Wide Web itself, the concept is simple – link data in such a way as to ensure the machines have the ability to not only recognize links between data, but to contextualize and understand them. In his 2006 note on Linked Data, Berners-Lee presents four basic principles for the establishment of such Linked Data: 
- Use URIs to name and identify content;
- Use HTTP URIs so that these named and identified content entities can be looked up;
- Utilize open standards such as RDF or SPARQL to provide useful information about what a name identifies to those who query the content;
- When publishing data to the web, refer to these things by their HTTP URI-based names.
First, the web supports a wide range of formats and systems. In order to support meaningful relationships, these formats need to be either standardized or widely supported, and either side creates additional issues. If you mandate a specific format, you’re excluding possibly powerful uses for those other formats, and if you allow any format to be used, you create segmentation in support.
Second, the fundamental nature in which this data is linked needs to be considered in order to establish these relationships. Simply linking content directly does not create a relationship – having Jens exist at http://internalwiki.com/Jens tells the API server nothing about the relationship, and simply serves as a one-way road. Thus, systems must used Linked Data as a default approach in order to participate and leverage the power of such a semantic relationship web – and as such, needs to tie into the consideration on formats as well.open data, sometimes Linked Open Data a system of open data that is Linked together.