People, or people, can be defined from the biological, spiritual and cultural levels, or the combination of these levels. Biologically, human beings are classified as Homo sapiens Linnaeus, a kind of primitive mammal primate with a highly developed brain. On the spiritual level, people are described as being able to use various concepts of souls, which are considered to be related to divine power or existence in religion; In mythology, the human soul will also be compared with other humanoid animals. In cultural anthropology, people are defined as people who can use language, have complex social organizations and scientific and technological development, especially they can establish groups and institutions to achieve the purpose of mutual support and help. In biology, the scientific name of Homo sapiens is Homo sapiens, which is a primate belonging to the hominid family with chimpanzees, gorillas, orangutans, gibbons and sea dragons. The difference between humans and other primates lies in their upright bodies, highly developed brains, and their reasoning and language skills. Because of the close relationship between humans and apes, zoologist D. Moliis jokingly called humans naked apes and wrote down the origin of human behavior from various angles. From the behavioral point of view, human beings are characterized by knowing how to use language, having various complex mutual social organizations and being fond of developing complex science and technology. These behavioral differences also lead to different beliefs, legends, rituals, values and social norms in different cultures. Juvenile males are called boys and adults are called men. Underage women are called girls, and adult women are called women. Usually, individuals or people are called individual human beings, and all human beings are called all human beings. In philosophy and law, people, people and individuals have different meanings. The former refers to this species, and the latter is an individual; For example, in John Locke's paper "About Human Understanding II 27" and Emanuel Kant's "Introduction to Moral Metaphysics", individuals are used to refer to some non-human animals, and can also refer to mysterious animals, artificial intelligence or aliens. An important question in theology and religious philosophy is whether God is an individual (see anthropoid personality). In Chinese characters, Oracle Bone Inscriptions's character "Ren" is an ideographic character, depicting a human figure standing sideways, deliberately highlighting human limbs. This simple and bright line combination has been maintained from inscriptions on bronze and seal script to regular script. Interpretation of Shuo Wen Jie Zi: "It looks like an arm and a shin." In Latin, humanus is an adjective of homo, which means a person (male or female). Man in old English also has this meaning, such as the compound word wifman → wiman → woman. For the etymology of man, please see mannaz. Human skeleton specimens. Human life begins with a fertilized egg. Men usually fertilize women through sexual intercourse, and sometimes artificial insemination is also possible. A person is called a fertilized egg in the early stage of growth. A fertilized egg lasts for 38 weeks in a woman's uterus and goes through various growth stages, and finally becomes an embryo and then a fetus. After becoming a fetus, you can be ready to be born. After the fetus was delivered from the body by a woman, it breathed spontaneously for the first time and was renamed as a baby. It is not until they become babies that people begin to be protected by law, and a few areas may be protected in the womb from the fetal period. Human life ends with death. Compared with other creatures, the production process of human beings is much more complicated. Painful childbirth lasting more than 24 hours is not uncommon, and sometimes it even causes injury or death to the child or mother. It was not until the 20th century that the production success rate in some developed countries was relatively high. Whether the production in other developing countries is really prone to failure is controversial, because women in these areas claim that the natural delivery methods they adopt are not only safer, but also less likely to cause harm to mothers and children. Death often brings uncomfortable feelings or fears (see near-death experience). Funeral is one of the characteristics of human society, which usually comes from the belief in the world after death. However, a person's living method can only be worshipped and passed down by future generations. People's appearance plays an important role in culture and art. People decorate their bodies with tattoos, make-up, clothes and jewelry. The difference between hair style and hair color also implies some cultural differences. Whether a person's appearance is beautiful or ugly has a great influence on his life. The demand for food and water is also reflected in human culture. If you don't get food, you will be hungry, and if you don't get drinking water, you will be thirsty and even dehydrated. Hunger or dehydration for too long can lead to death; Humans can live for two months without food, but they will die in 14 days at most without water. Adults sleep seven to eight hours a day on average, while children sleep about nine to ten hours. Older people sleep about six or seven hours. But usually modern people don't get enough sleep. People will get old and get sick, which will lead to the decline of physical condition. Medicine is a science that studies how to keep healthy. Early modern people used "hunting" as the main way to collect food, combining fixed food sources, plants and molds (such as fruits, grains, tubers and mushrooms) and hunting other animals. It is generally believed that modern people cooked food with fire from the branch of Homo erectus. Man is an omnivore and can digest plants and animals. People have the important characteristics of omnivores. A vegan or vegan will lead to physical deficiency diseases. Vegetarian diet can lead to scurvy, and vegetarian diet can lead to a certain amount of nutritional deficiency, including vitamin B 12. Especially vitamin B 12, as a vegetarian, you must always supplement it. Some people choose not to eat some or all meat, usually for religious, moral, ecological protection or health reasons. Human diet is reflected in regional culture, which also leads to the development of food science. Generally speaking, people can live for two to eight weeks on the basis of storing fat, but generally less than two weeks without drinking water. Nowadays, food shortage is still a serious problem. Every year, 300,000 people face the threat of death because of hunger. Child malnutrition is a worldwide problem. However, the global food distribution is uneven, and the proportion of obesity diseases in some countries is very high. By 10,000 years ago, people had developed agriculture, and agricultural technology greatly increased human food sources. This has led to the rapid growth of population and the development of cities; Due to the increase in population density, the spread of infectious diseases has accelerated. In different times, different regions, different nationalities, food culture has undergone extensive changes. Except Antarctica, human beings have settled and lived in most parts of the earth for a long time. Most of the plains are densely populated areas, and two-thirds of the people in the world live within 500 kilometers from the coastline. The mountainous and plateau areas are sparsely populated. At present, there are about 7,200 languages used by human beings, of which only about 2,000 have their own characters. The most widely distributed languages in the world are English, Spanish, Arabic, Portuguese, Chinese, Russian, French and German. According to the analysis of 6,809 languages by William Sutherland, a population ecologist at the University of East Anglia, nearly 1/3 languages are in a very dangerous situation, and only one person can master 46 languages. The number of human species is called population. The world population exceeds 7 billion, and the United Nations estimates that it will reach 90 to 654.38+0 billion in 2050. In 2004, the most populous countries were People's Republic of China (PRC) (131300 million), India (1081000 million), the United States (300 million), Indonesia (223 million) and Brazil (1868). The country with the largest population density is Monaco, a small European country. Generally speaking, the population growth rate in developed countries and regions is very slow, and many countries even have negative growth. However, the growth rate of underdeveloped areas has not slowed down. From 2000 to 2005, the average population growth rate of developed countries and regions was -0.2%, while that of underdeveloped regions was 1.5%. According to the world population situation of the United Nations Population Fund in 2004, the total world population in 2004 was 6.378 billion. Among them, there are 654.38+206 million people in developed areas. There are 565,438+72 million people in underdeveloped areas. In 2005, about 259 people were born every minute in the world, and about 38 people were born every minute in People's Republic of China (PRC). Population aging is an increasingly serious social problem. At present, the country with the most aging population in the world is Morocco, with the population over 65 years old exceeding 22%. Italy and Sweden also exceeded 17%. The United Nations predicts that in 2050, the proportion of people over 60 will increase from 10.0% to 22. 1%. I hope my answer is helpful to you! ! ! !