Intelligence means both the product and the process of systematically collecting, collating and analysing raw
information so as to understand a situation.
The term is more commonly used in the context of protecting and supporting a country's national interests (military intelligence, which includes the 'big picture' strategic intelligence and 'battlefield' tactical intelligence). Law enforcement agencies apply criminal intelligence in fighting crime. Recently the term has also been applied to the activities businesses carry out in understanding and quantifying the markets they are targetting.
Information - which would come from many different sources - needs to be documented as it is received. Its authenticity, relevance and contemporaneousness is evaluated, usually by assessing the reliability of the source and/or how it contradicts or complements known facts. Different sources produce different types of intelligence:
HUMINT: Human Source Intelligence - gaining information from people, through bribery, blackmail, encouraging defections etc.
SIGINT: Signal Intelligence - evesdropping on electronic communications.
IMINT: Imagery Intelligence - using satellites, aircraft, pilotless drones and other assets to intensively view a geographical region. IMINT is used more frequently now thanks to technological innovations.
MASINT: Measurement and Signature Intelligence - analysing the use of radio-communication devices (such as signal strength, rather than what is being said)
OSINT: Open source Intelligence. Researching from what has already been published.
In putting each piece of worthwhile intelligence together, an appreciation is formed. With a better understanding of the situation, an intelligence analyst might then seek additional information by redirecting intelligence assets to concentrate on certain targets or patterns. Simulataneously, in the real world circumstances change and the appreciation needs to be constantly updated. The whole cyclical process is known as the intelligence cycle, and can be broken down into stages:
Planning and Direction
Collection
Processing
Analysis
Dissemination
Counter-Intelligence is the process of detecting and preventing a rival organisation from gaining sensitive information and intelligence about your own country.