What is the Wikipedia general notability guideline vs specific notability guidelines?

Wikipedia has a tiered notability system. The General Notability Guideline applies to all subjects by default: significant coverage in multiple reliable, independent secondary sources. The subject-specific notability guidelines provide alternative paths for specific categories where the source profile is different. Academics have a separate notability guideline that emphasizes citation patterns and academic impact rather than mainstream press coverage. Athletes have one based on competitive level and competition records. Politicians have one based on the level of office. Books, films, and other creative works each have their own. Companies fall under a stricter version of GNG that emphasizes in-depth independent coverage and explicitly excludes routine business announcements. Picking the right guideline at the start changes which sources matter.