While growing up I was taught that there are 3 types of angels: Seraphim, Angels, and Cherubim. Among those 3 kinds there's a hierarchy of orders, positions, or jobs given to each by God individually.
☆ Seraphim are the most beautiful and luminescent of angels, bearing six wings on their body (two on their back - two on their hips - and two on their feet) to carry out a special mission God appoints this sparse but powerful class of angels. A common order assigned to Seraphs is to be the steward of a nation, for example, the Angel of Portugal.
☆ Angels or regular angels are the most common type of angels, bearing only two translucent wings on their backs for their conventional but specific mission God appoints each of them. One common position of an Angel is that of a lifelong guardian, for example, a Guardian Angel.
☆ Lastly Cherubs or Cherubim, the smallest and closest to God's heart, bearing two small wings in proportion to their youthful semblance. They're the most free of all the angels, swiftly piercing in & out of Heaven innocently to their heart's content. A common job given to Cherubims is that of a messenger, for example, telling someone to look both ways before crossing a busy street.
Of these 3 types of angels, active in a myriad of orders, God chooses 7 to be his Archangels; Seven temporary rotational positions, depending on the unique need of humanity & creation at the present time. Only angels that have sacrificed their wings for someone else, an extremely hard and almost impossible thing to do for any kind of angel, are chosen by God to become Archangels. Once their task is fulfilled, their original wings reappear in an even brighter color, and the position is passed on ～ ♪