A pentacle is a a five-pointed star, within a circle. A Pentagram is a five pointed star without a circle. It is a sign of protection for witches and pagans. Pentagram symbols has been found on Sumerian pottery from 3500BCE and has been connected to multiple Mesopotamian gods like Inanna, who are still present in the current practice of witchcraft. In 300-150 BCE the pentagram stood as the symbol of Jerusalem, marked by 5 Hebrew letters. And in the middle ages it was a christian symbol for the five senses or the five wounds of christ. 

In witchraft the pentacle symbolizes, besides protection,  the five elements—earth, air, fire, water, and spirit—or the open human being, connecting all aspects of existence. Pentacles can even be found in churches and are employed in different contexts, including witchcraft, Wicca, and, inversely, in Satanism.

On an altar, the pentacle represents the elements and the spirit that interconnects them, serving as a powerful emblem of unity and balance in ritual practices.