Snack is a kind of food with specific style and characteristics in taste. Local snacks can highlight the local material, culture and social life, which is an indispensable feature of a region and the main target of homesickness for homeless people. There are all kinds of snacks around the world, which are different from local customs and have distinctive features and unique flavors. Modern people usually don't eat snacks to satisfy their hunger. Besides satisfying their desires, they can also learn about local customs by tasting snacks with different local flavors. Snacks have three explanations in Modern Chinese Dictionary, which refers to "the general name of rice cakes, zongzi, Yuanxiao, hot and sour powder, camellia oleifera and other foods sold in catering industry". Beijingers also call snacks "dinner", which probably refers to "cold dishes" different from the staple food. There are many kinds of snacks, including all kinds of food, fruits and vegetables, meat, eggs and milk. They are all sweet, sour and spicy, and they are eaten in different ways, far exceeding the definition of "snack" in the dictionary.