The time zone that corresponds to GMT +0 is Greenwich Mean Time (GMT) itself. GMT serves as a reference point for various time zones around the world, with zero hours offset from the Prime Meridian in Greenwich, England. This time standard does not observe Daylight Saving Time, making it a stable reference throughout the year. Cities in the GMT +0 zone include London and Lisbon, making them significant locations in global scheduling and international relations. Many countries use GMT as a basis for their local time calculations, setting their clock accordingly.