Biographical intelligence is a subset of intelligence analysis based on knowing, and recording, every possible name, nickname, code, and other identifiers for individuals. The challenge is "connecting the dots" and creating the "wiring diagram" among these identifiers. British intelligence, one of the first to organize this information, called the collection the "Registry", and this name has come into general use. Even a chance mention of a name on a captured document or a broadcast should cause a name record to be created, although there should be an active effort to link the formal and informal names:
Intelligence services assume there will be spelling and pronunciation variations of names. As well as their best understanding of the correct spelling, and any specifics such as serial number, their data bases usually employ additional phonetic coding methods, such as Soundex. Individual identifying information, such as fingerprints, DNA, voiceprints, writing patterns, etc., are also sought.
The challenge of naming becomes more complex when the opponent uses a language that does not use Roman letters and transliteration becomes necessary, and even when a Roman alphabet language has common spelling variations on similar-sounding names, such as Gomez and Gomes.
Aliases, of course, are a great complication, especially when dealing with clandestine organizations.
Family relationships are important, both for understanding the individual and possible patrons or enemies, but also in identifying individuals that use not conventional personal and surnames, but relationship oriented names such as Abu Zubaydah (father of Zubaydah) or Dmitri Pavlovich (Dmitri, son of Pavel).
Biographical information is a "bottom-up" feeder into order of battle intelligence.
Reading every scrap of written information (called "document exploitation" for captured materials and open source intelligence for public data) and prisoner interrogation are the core collection methods, considered human-source intelligence. Other human-source methods, such as elicitation of information from cooperative persons complement the process.
Signals intelligence plays a vital role, both of human communications and of electronic intelligence such as traffic analysis of telephone numbers and radio addresses, as well as characteristics of electronics used (e.g., satellite or cellular telephones).
Imagery intelligence starts with pictures of persons, insignia, then of vehicles and other individual equipment. More general information can be informative; Soviet S-75 Dvina air defense missile sites had a characteristic layout, so if imagery revealed construction of such a site, the communications and human intelligence collectors were alerted to the presence of anti-aircraft specialists.