Baphomet, also known known as the "Sabbatic Goat" is a demonic entity, a king of demons, usually equated with Satan and an idol adopted by the Knights Templar from Islamic belief.
His name is believed to be a corruption of Muhammad, the founder of Islam. He is usually depicted with the head and legs of a goat, with a torch between his horns and a pentagram on his forehead, with black bird wings, and the body of a human woman or hermaphrodite.
He has the power to control all human women, and is said to give witches their power, thus, famously known as a demon worshipped by witches.
Baphomet is a goat-headed demon who was worshipped by practitioners of the occult, although there was little evidence of this actually occurring until later in history. He was also supposedly the secret benefactor of the Knight Templars during the height of the persecution against the Order.
The Knights Templar, heroes of the Crusades, were accused of worshipping Baphomet by a church Inquisition and branded as heretics. To keep them silent, the head of the Templars and another senior leader were sentenced to be burned alive. However, it was later revealed that this was orchestrated by King Philip IV of France, who coveted the Templars' wealth and moreover was purportedly under the influence of Baphomet himself who used the king to twist the image of the Templars and their faith.
Despite this, Baphomet became popular among those who opposed orthodox religion or order, and became a patron of many different Left-Hand faiths. Among them is theistic Satanism, where he was seen as either a symbol or a literal being depending on the beliefs of the cult and could vary in function. In some branches of demonology, Baphomet is seen as a high-ranking ruler of Hell and one of Satan's many henchmen. This may go some way into explaining why the two demons often seem to share the same qualities.