Information extraction systems analyze unrestricted text to extract information about pre-specified types of events, entities, or relationships.

the extraction or pulling out of pertinent information from large volumes of texts

Culling concepts from unstructured data.

Culls concepts, such as names, geographic entities and relationships, from unstructured data (mostly text).

In computer science, information extraction (IE) is a type of information retrieval whose goal is to automatically extract structured information from unstructured machine-readable documents. An example of information extraction is the extraction of instances of corporate mergers, more formally MergerBetween(company_1, company_2, date), from an online news sentence such as: "Yesterday, New-York based Foo Inc. announced their acquisition of Bar Corp."