I
In education, the ability to learn or understand or to deal with new or challenging situations.
In psychology, the term may more specifically denote the ability to apply knowledge to manipulate one's environment or to think abstractly as measured by objective criteria (such as the IQ test). Intelligence is usually thought of as deriving from a combination of inherited characteristics and environmental (developmental and social) factors. The subject remains hotly debated, and many have tried to show that either biology (especially genes) or environment (especially conditions reflecting socioeconomic class) are more or less exclusively responsible for producing differences in intelligence. Particularly contested have been studies purporting to show links between ethnic heritage and intelligence, most of which have not been accepted in the scientific community. General intelligence is often said to comprise various specific abilities (verbal ability, ability to apply logic in solving problems, etc.), but critics contend that such compartments fail to reflect the nature of cognition and that other models, perhaps based on information processing , are needed. High intelligence (as measured by tests) is sometimes shown to correlate with social achievement, but most experts believe other factors are important and that intelligence is no guarantor of success (and its lack is no guarantor of failure). See also creativity .
II
In government and military operations, evaluated information concerning the strength, activities, and probable courses of action of international actors that are usually, though not always, enemies or opponents.
The term also refers to the collection, analysis, and distribution of such information and to the secret intervention in the political or economic affairs of other countries, an activity commonly known as "covert action." Intelligence is an important component of national power and a fundamental element in decision making regarding national security, defense, and foreign policies. It is conducted on three levels: strategic, tactical, and counterintelligence. Despite the public image of intelligence operatives as cloak-and-dagger secret agents, much intelligence work involves an undramatic search of "open" sources, such as radio broadcasts and various publications. Among covert sources of intelligence are imagery intelligence, which includes aerial and space reconnaissance, signals intelligence, which includes electronic eavesdropping and code breaking, and human intelligence, which involves the secret agent working at the classic spy trade. Leading national intelligence organizations are the Central Intelligence Agency (CIA) in the U.S.; the Federal Security Service in Russia; MI5 and MI6 in Britain; and the Mossad in Israel.
III
[c mediumvioletred] (as used in expressions)
{{link=intelligence quotient">intelligence quotient
Military Intelligence Unit 5
search for extraterrestrial intelligence
artificial intelligence
Central Intelligence Agency