Non-human intelligent being
A non-human intelligent being (NHIB) is an intelligent being who is not human. NHIBs are often described as members of one or more species alleged to exist beyond the scope of mainstream understanding, with reported origins ranging from other celestial bodies to alternate dimensions or timelines. Extraterrestrial humans, while considered extraterrestrial beings, are not classified as NHIBs. Similarly, subterranean humans would not be NHIBs. NHIBs are most commonly alleged to be extraterrestrial in origin, often described as belonging to advanced civilizations or species of NHIBs capable of interstellar travel and communication. However, not all NHIBs are necessarily extraterrestrial. Some are alleged to be cryptoterrestrials—beings that inhabit hidden or unexplored regions of Earth—or interdimensional beings theorized to exist beyond conventional space–time.
The concept of NHIBs is central to numerous conspiracy theories that suggest that NHIBs play a hidden but significant role in the development of human civilization, technology, and culture, are being hidden by the powers-that-be, and/or are acknowledged as real and factual by the private civilization. Many are frequently alleged to possess advanced technology and knowledge, with many claims emphasizing their ability to remain hidden from mainstream detection.
Many different species of NHIBs in many communities have been alleged, ranging from Zeta Greys and mantis beings to less anthropomorphic forms, such as energy beings or non-biological entities. These beings are often categorized by their level of intelligence, physical form, and interaction with humanity.