What does Islam teach about angels?

As a believer, one is to believe in the existence of the angels, who are bodies of light and inhabit the heavens. The Beloved Prophet ﷺ said, "There is no space of a hand span in the heaven but is occupied by an angel who is prostrating." [Riyad as-Salihin 406]

Sayedda Ayesha may Allah be pleased with her reported that the Beloved Prophet ﷺ said, "Angels were created from light, jinns were created from a smokeless flame of fire, and Adam was created from that which you have been told." [Riyad as-Salihin 1846]

Angels are honourable slaves of Allah who execute their duties perfectly without objection. They are neither male nor female, nor do they eat or drink. They worship Allah continuously and celebrate His praise day and night without boredom or exhaustion.

They execute certain chores and perform assigned tasks, for example registering the future of the foetus, assisting believers, recording man's deeds, death and grave duties, attending the circles of dhikr and guarding Madinah, and Allah knows best.

They are so many that only Allah knows their number. Allah mentions in the Qur'an: "No one knows the troops of your Rubb except He." [Qur'an, al-Muddaththir 74:31]

Just to give an idea, there is a place in the seventh Heaven called al-Bait al-Ma'moor, the Continuously Occupied House, about which the Beloved Prophet ﷺ said, "Seventy thousand angels enter it every day and never get the chance to re-enter it again." [Sunan Ibn Majah]