What is relation extraction? Application, Description

Relation extraction plays an important role in extracting structured information from unstructured sources such as raw text. For example, interactions between drugs, understanding scene, relationships among people.
http://deepdive.stanford.edu/relation_extraction

TAC KBP SF - Text Analysis Conference Knowledge Base Population Slot Filling

by US National Institute of Standards and Technology

goal of KBP : populating knowledge bases from unstructured text.
slot filling : to search the document collection to fill in values for specific attributes("slots") for specific entities.