Since ancient times, people have tried to explain the unusual or frightening phenomena of nature by the manifestation of supernatural forces. The concept of "religion" appeared relatively recently, and the religions themselves were born and formed quite a long time ago.
Religion (from Lat. Religio - piety, shrine) is a form of social consciousness, a set of spiritual ideas based on belief in supernatural forces and beings (spirits and gods) that are the subject of worship. Thus, the term "religion" means the worship of the gods. It is closely related to the concepts of "God" and "faith".
At the dawn of mankind, people explained drought and flood, sunset and sunrise, thunder and lightning by the actions of good and evil gods. There were also "special" people - shamans, who knew how to communicate with the other world (with gods and ancestral spirits). Their task was to appease these gods and predict fruitful and lean years, wars or natural disasters. Each phenomenon was associated with a certain deity (god of thunder, god of war, god of the sun, etc.). These beliefs in a plurality of gods are called paganism or polytheism. Think of the ancient Greek, Egyptian, Sumerian or Aztec gods. Gradually, shamans turned into priests, temples into temples, and dancing around the fire into rituals. But the essence remained the same - belief in numerous gods and goddesses.
With the development of civilized society, the need for several gods disappeared, monotheism appeared - the belief in a single god. It is believed that the first in this were the Jews with their faith in the god Yahweh. Attempts to introduce monotheism in Egypt (the cult of the single sun god Ra) were unsuccessful. Monotheism was not only religious, but also political. The unification of tribes and territories was required under the auspices of one state. But each tribe, each village lived its own life, and each community had its own beliefs and its own gods. Belief in one god was able to unite and unite people, made it possible to call each other brothers. And so the priests turned into priests, rituals into ceremonies and sacraments, spells into prayers.
There is a conventional wisdom about 3 worlds, i.e. the most numerous religions are Buddhism, Christianity and Islam. But based on the definition of the term religion, this is not entirely correct. Although Buddhism is very numerous, it is not a religion. Buddhism, like Taoism, Hinduism, Shintoism, is a teaching, a belief in the forces of nature, and not a specific god. Otherwise, it can be called a religion without a god. And Christianity, which was originally a teaching, later became a religion. Representatives of modern monotheistic religions include: Judaism, Christianity, Islam and Sikhism. While polytheistic religions died out. Recently, such a phenomenon as "neo-paganism" has appeared. This trend is increasingly spreading not only in Europe, but also in Russia.