YAGO is a huge semantic

Semantics

Semantics is the study of meaning. It focuses on the relation between signifiers, such as words, phrases, signs and symbols, and what they stand for, their denotata....

 knowledge base

Knowledge base

A knowledge base is a special kind of database for knowledge management. A Knowledge Base provides a means for information to be collected, organised, shared, searched and utilised.-Types:...

. Currently, YAGO knows over two million entities such as person

Person

A person is a human being, or an entity that has certain capacities or attributes strongly associated with being human , for example in a particular moral or legal context...

s, organization

Organization

An organization is a social group which distributes tasks for a collective goal. The word itself is derived from the Greek word organon, itself derived from the better-known word ergon - as we know `organ` - and it means a compartment for a particular job.There are a variety of legal types of...

s and cities

City

A city is a relatively large and permanent settlement. Although there is no agreement on how a city is distinguished from a town within general English language meanings, many cities have a particular administrative, legal, or historical status based on local law.For example, in the U.S...

 and about twenty million facts about these entities. A web interface allows users to pose questions to YAGO in the form of queries on the YAGO homepage. YAGO is being developed at the Max Planck Institute for Computer Science

Max Planck Institute for Computer Science

The Max Planck Institute for Computer Science is devoted to cutting-edge research in computer science with a focus on algorithms and their applications in a broad sense...

.

YAGO is automatically extracted from Wikipedia

Wikipedia

Wikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. Its 20 million articles have been written collaboratively by volunteers around the world. Almost all of its articles can be edited by anyone with access to the site,...

 and uses WordNet

WordNet

WordNet is a lexical database for the English language. It groups English words into sets of synonyms called synsets, provides short, general definitions, and records the various semantic relations between these synonym sets...

to structure information.