Rabbinical demonology, which was heavily influenced by the ancient Chaldean (Babylonian) religious system, states that there are three main classes (types) of demons. They are the shedim, the mazzikim (harmers) and the ruhin (evil spirits). Besides these, spirits were classified based on the time of day in which they were active (morning, midday, evening and night spirits).
The king or ruler of all the demons is called Adhmodai, or, in still older traditions, Samael (Satan). He is considered an enemy of man but not an opponent of God or what is good. According to tradition, his "fall" took place not before the creation of man (which is what the Bible teaches - Ezekiel 28:14 - 16, Isaiah 14:12 - 14, Luke 10:18) but after it.
Lilith is considered the queen of the demons. Her name is taken from the Hebrew word liyliyth (Strong's Concordance #H3917) found only in Isaiah 34:14. The KJV Bible translates the word as "the screech owl." Jewish tradition, however, holds that the word means "night specter" (night demons or monsters) and that it refers to a well-dressed woman who, at night, can carry off children or those who sleep alone in order to harm them.
Additionally, evil spirits, according to rabbinic teaching, can be either male or female (Scripture teaches that all spirits, including God, are sexless). Instead of their number being fixed it is taught they were allowed to greatly multiply through male spirits procreating with Eve and female spirits reproducing themselves through Adam before the birth of Seth (Genesis 5:3).
Concerning the vast number of disobedient spirits taught by the Rabbis, the Catholic Encyclopedia states, "One characteristic of Jewish demonology was the amazing multitude of the demons. According to all accounts every man has thousands of them at his side. The air is full of them, and, since they were the causes of various diseases, it was well that men should keep some guard on their mouths . . ." (article on Demonology).
The saiyr, Strong's Concordance #H8163, literally "the hairy ones," are demons who are worshipped through idols (idolatry). Jeroboam, the first king of the Northern Ten Tribes of Israel, not only created his own version of the priesthood that existed in Jerusalem, but also commanded that they help the people worship such spirits through idols (2Chronicles 11:15).
The shedim (or shed), Strong's #H7700, literally means "devil" or, according to the 1906 Jewish Encyclopedia, "storm demons." They, too, were worshipped by the Israelites (Deuteronomy 32:17, see also Psalm 106:37).
Demons can also be referenced as spirits that are evil (Judges 9:23), lying (1Kings 22:22 - 23), perverse (Isaiah 19:14), unclean (Zechariah 13:2) or familiar (Leviticus 20:6).
Two broad categories of demons exist based on the level of freedom they have to carry out their evil desires. The first are those who have been given a measured amount of freedom to deceive, possess and bring trials to humans (Ephesians 6:11 - 12). The devil and at least some fallen angels are in this first category.
The second broad category of demons is those who are being restrained (imprisoned) by the Eternal. Some of these wicked or unclean spirits WILL be let loose in the very near future. God will release them, during the prophetic period known as the Day of the Lord, in order to punish humans for refusing to repent (Revelation 9:13 - 15, see also verses 1 to 4).
Still other disobedient spirits or demons are being restrained will not be taken out of their spiritual prison until the time of their ultimate judgment (2Peter 2:4, Jude 1:6).