Angels, like dreams, are immaterial things.

An angel is a supernatural being found in many religions. In Christianity, Islam, Judaism, and Zoroastrianism, angels, as attendants or guardians to man, typically act as messengers from God. In some cultures, they are believed to be the most powerful type of fairy.

The English word came from Latin angelus, which came from Greek ἄγγελος, ángelos, meaning "messenger".

In the Bible, angels are a medium of God's power; they exist to execute God's will. Angels reveal themselves to individuals as well as to the whole nation, to announce events, either bad or good, affecting humans. Angels foretold to Abraham the birth of Isaac, to Manoah the birth of Samson, and to Abraham the destruction of Sodom. Guardian angels were mentioned, but not, as was later the case, as guardian spirits of individuals and nations. God sent an angel to protect the Hebrew people after their exodus from Egypt, to lead them to the promised land, and to destroy the hostile tribes in their way.

Biblical books present angels as heavenly beings created by God, who are not endowed with free will.

The archangels named in post-exile Judaism are Gabriel, Michael, Raphael, Uriel, Raguel, Sariel, and Jerahmeel. Gabriel and Michael are mentioned in the book of Daniel, Raphael in the book of Tobit (from the Protestant Apocrypha or Catholic and Orthodox Deuterocanon) and the remaining four in the book of Enoch from the Old Testament Pseudepigrapha (considered canonical by the Ethiopian Orthodox).

Catholic theologians have long speculated that there are nine ranks of Angels; Angels, Virtues, Powers, Principalities, Dominations, Throne, Cherubim, Seraphim and Archangels. This is not official Church doctrine or dogma, however, and in general the faithful are not required to adhere to this categorization.

Although most theologians in the cultures mentioned above (Latter-day Saints excepted; see above) would agree that angels are technically genderless in the normal human sense, all references in the Jewish, Christian and other holy writings mentioned above give angels a masculine aspect; for example, angels are given tasks such as warrior, herald, guard (at the gates of Eden), wrestler (of Jacob), mover of large stones (at the tomb of Christ), which in traditional societies would all have been tasks typically performed by men. The few canonical names of angels (e.g., Michael, Gabriel and Lucifer) are recognized in most cultures as masculine names. In languages with gender markings for nouns, the word "angel" is uniformly a masculine noun, including in the original Hebrew, Greek and Latin texts referred to above. In cultures where the proper name "Angel" is given to children, the name "Angel" is typically given to boys (girl's versions of the name include "Angela" and "Angelica"). The word "angel" in English, French, German, Spanish, and many other European languages is derived from the Latin angelus, a masculine noun.

In art, however, angels are always beautiful, which tends to mean their features are often rather feminine - even for warrior archangels, their hair is usually long, and their figures somewhat slight. In European medieval and Renaissance paintings of the Annunciation the archangel is usually depicted as noticeably more attractive than Mary - she could not be painted in a way that might inspire lustful thoughts, whilst no such problem arose with a genderless angel. Angels in art become more sexually differentiated from the nineteenth century, after which breasts and masculine figures and haircuts appear. In modern Western culture, many angels are depicted as having female figures, facial features and names, and many New Age practitioners speak of masculine and feminine angels.

Source : http://en.wikipedia.org