다음 글의 제목으로 가장 적절한 것은? Mapping technologies are being used in many new applications. Biological researchers are exploring the molecular structure of DNA ("mapping the genome"), geophysicists are mapping the structure of the Earth's core, and oceanographers are mapping the ocean floor. Computer games have various imaginary "lands" or levels where rules, hazards, and rewards change. Computerization now challenges reality with "virtual reality," artificial environments that stimulate special situations, which may be useful in training and entertainment. Mapping techniques are being used also in the realm of ideas. For example, relationships between ideas can be shown using what are called concept maps. Starting from a general or "central" idea, related ideas can be connected, building a web around the main concept. This is not a map by any traditional definition, but the tools and techniques of cartography are employed to produce it, and in some ways it resembles a map.