Methods of Gathering Information
Intelligence means are disciplines or human sources and tools for gathering information. The international terminology uses English abbreviations with the ending INT (which is an abbreviation of intelligence), with one exception, for these methods. The methods are Open Sources Intelligence - OSINT, Human Intelligence - HUMINT), Signal Intelligence - SIGINT), Image Intelligence - IMINT and the international cooperation between intelligence services - LIASON.
Source: Petr Zeman - lectures, trainings and public speeches