Semantic networks, which originally have been developed to represent associative memory, are notation systems used for knowledge representation. Within these representation schemes a hierarchy of concepts is used that is organized by simple relations such as IS-A or PART-OF (a bird IS AN animal, a robin IS A bird). Thus, concepts are represented by nodes, while the relations between these concepts are notated by links that represent hyponymy relations.
The most important aim in developing semantic networks is to establish the inventory of semantic relations between concepts. As it is assumed that attributes associated with higher nodes are also valid for lower nodes, deductions can be made rather easily. This aspect is called property inheritance. By virtue of property inheritance, the amount of properties is reduced and redundancy is avoided.