Firecrackers are a special product of China. They are also called "bursting weapons" and "cannon weapons" etc. Exploding firecrackers is an important custom during the Spring Festival, dating back over 2,000 years. Firecrackers were originally used to drive away poisonous mists or curb pestilence. Later, with the appearance of gunpowder, niter, sulphur and charcoal etc were filled into the firecracker bamboo pipe for explosion. Thus, "bursting weapons" were produced. As the blasting sounds are perfect for creating joyous atmosphere, exploding firecrackers has become a recreational activity with national characteristics. Nowadays, apart from letting off firecrackers during the Spring Festival to welcome the New Year, people also like to explode them for celebrations on weddings, foundation-laying ceremonies and grand openings etc.