Information Extraction (IE) is a natural language processing (NLP) technique that involves automatically extracting structured information from unstructured text.

Information extraction is the technique of creating database entries. 

The goal of information extraction is to transform raw textual data into useful information by identifying and extracting specific pieces of information, such as entities, relationships, and events.

The field such as street, city, state, pin-code are extracted from instances of addresses from web pages. 

The instance of weather report with temperature, wind, speed, humidity are extracted. 

Information retrieval systems and full text parser can be mapped by mid system called information extraction.