Ba'al is a title meaning "lord" that was applied to a number of West Semitic gods.
Baal Hadad, probably the most widely-worshiped Baal, was worshiped by Arameans who brought his worship to other parts of the Mediterranean. Early demonologists, unaware of Hadad or that the instances of the term "Ba'al" in the Bible referred to any number of local deities, few to none of them referring to Hadad, came to regard the term as referring to but one personage. Until archaeological digs at Ras Shamra and Elba uncovered texts explaining the Syrian pantheon, the Ba‘al Zebûb (or Beelzebub) was frequently confused with various Semitic gods Ba'al, and in some Christian writings it might refer to a high-ranking devil or to Satan himself.
The Biblical and historical evidence shows that the Moabites worshiped a Baal. The pre-Islamic and Muslim sources show (a) that the Meccans took over the idol Hubal from the Moabites.
Baal is a Christian demon. According to Christian demonology, Baal (usually spelled "Bael" in this context; there is a possibility that the two figures aren't connected) was ranked as the first and principal king in Hell, ruling over the East. According to some authors Baal is a Duke, with sixty-six legions of demons under his command. The term "Baal" is used in various ways in the Old Testament, with the usual meaning of master, or owner. It came to sometimes mean the local pagan god of a particular people, and at the same time all of the idols of the land. It is also found in several places in the plural Baalim, or Baals (Judges 2:11, 10:10). There were many variations, such as the sun god, the god of fertility, and Beelzebub, or the "lord of flies".
During the English Puritan period, Baal was either compared to Satan or considered his main assistant. According to Francis Barrett, he has the power to make those who invoke him invisible, and to some other demonologists his power is stronger in October. According to some sources, he can make people wise, speaks hoarsely, and carries ashes in his pocket.
While his Semitic predecessor was depicted as a man or a bull, the demon Baal was in grimoire tradition said to appear in the forms of a man, cat, toad, or combinations thereof. An illustration in Collin de Plancy's 1818 book Dictionnair Infernal rather curiously placed the heads of the three creatures onto a set of spider legs.
The idea of Baal as a demon was created when Christianity turned ancient gods into demons and demonology divided the demonic population of Hell in several hierarchies. Baal, the Semitic god, did not escape, becoming a separate entity from Beelzebub.