TABLE 6.

Description of the key characteristics of knowledge networks and graphs.

Main characteristics of knowledge networks and graphs
Nodes	Chemical compounds and chemical classes
Edges	Class membership (subsumption) and other optional semantic relations
Main Hypothesis	Knowledge can be organized and represented as a network/graph by manual curation from domain experts and semi-automatic class assignments
Limitations	Ontologies representing the same things might still differ and can be mapped to different concepts