The domestication of crops by humans was the origin of agriculture, and represents a key turning point in the transition from hunter-gatherer to agrarian civilizations. Although there are approximately 30,000 edible plant species worldwide, humans have relied on only 30 to sustain the global population. Among them, five major cereals — wheat, rice, corn, sorghum, and millet — provide 60% of the total energy for the global population. Bread wheat (Triticum aestivum L.) is one of the most pivotal crops, providing 20% of the calories and protein consumed by humans. As an allopolyploid hexaploid species, bread wheat contains three subgenomes (A, B, and D). Its formation involved two consecutive polyploidization events, endowing it with strong adaptability that allows it to be widely distributed worldwide — from inland areas to coastal regions, and from basins to plateaus, wheat can be found everywhere. As one of the earliest domesticated crops by humans, wheat drove the transition of humans from hunter-gatherer societies to agrarian societies, marking the beginning of the development of human civilization. This Primer will outline wheat’s origin and domestication, spread and adaptation mechanisms, yield-determining factors, as well as the challenges and corresponding responses in future wheat agricultural production.