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Based on the principle of rockets, the Chinese were the first to invent rockets. The name rocket first appeared in ancient Chinese classics during the Three Kingdoms period (AD 220- 265), but the so-called rockets at that time were just flammable materials tied to the front ends of arrows, and then shot out with bows or crossbows. There are no records of rockets using gunpowder until the end of the Tang Dynasty and the beginning of the Song Dynasty (10th century AD). For example, officers Feng Jisheng, Yue Yifang, and Tang Fu of the Northern Song Dynasty presented rockets and rocket techniques to the court, but these rockets only used gunpowder instead of flammable materials. , the rocket itself is still shot using a crossbow. Although the specific age is still debated, by the 12th century at the latest, rockets that used gunpowder as fuel and used jet action to fly had appeared.