Web-scale information extraction systems like NELL (Carlson et al., 2010) or Knowledge Vault (Dong et al., 2014) can acquire massive amounts of machine-readable knowledge from the Web, whereas projects like DBpedia (Bizer et al., 2009), YAGO (Rebele et al., 2016) or BabelNet (Navigli and Ponzetto, 2012) have turned collaboratively-generated content into large knowledge bases.
all of these resources are entitycentric in that they are primarily built around the notion of entities, as either provided by an external resource (e.g., Wikipedia pages) or automatically discovered from text (e.g., by clustering entity mentions).