Angels are dignified beings that Allah created out of light. Angels never disobey Allah, and do not tire from continuously glorifying Him.
"The Angels were created from light..." (Hadith)
They (the Angels) glorify His Praises night and day, (and) they never slacken (to do so). (Quran 21:20)
Angels never sin; whoever disbelieves in the Angels is a disbeliever.
They (the Angels) do that which they are commanded. (Quran 66:6)
Whosoever is an enemy to Allah and His Angels and His Messengers, to Jibreel (Gabriel) and Mikaeel (Michael), then verily, Allah is an enemy to the disbelievers. (Quran 2:98)
Angels have their own attributes (including wings) and sizes, but can appear in the shape of men, as did Jibreel (the Angel Gabriel) who brought revelation to the Prophets.
All Praise belongs to Allah, the Maker of the Heavens and the Earth, Who employs the Angels as messengers, with two, three or four wings. (Quran 35:1)
The Angels pray for the Believers, witness their pious deeds and give support and protection to them.
When your Lord revealed to the Angels, "I am with you, so give support to those who believe..." (Quran 8:12)
... and the Angels glorify the praises of their Lord and ask forgiveness for those (Believers) on Earth. (Quran 42:5)
The Angels curse disbelievers and send destruction to disbeliving nations by Allah's permission.
Verily those who disbelieve, and die while they are disbelievers, it is they upon whom is the Curse of Allah and of the Angels and of Mankind combined. (Quran 2:161)
Some Angels are assigned to supervise foetuses in the womb and begin writing their records at four months.
"... the Angel writes all of this (whether male or female, doomed (to Hell) or blessed (for Heaven), its provisions and its lifespan) while the child is in the womb of his mother." (Hadith)
Two Angels are assigned to every person to record his/her lifes' entire deeds.
When the two recording Angels record the deeds of Man, one sitting on the right and the other on the left... (Quran 50:17)
Some Angels are assigned to question the dead in their graves and some to remove their souls.
And He is the Supreme over His slaves, and He sends guardians to watch over you, until when death comes to any one of you, Our messengers (Angels) take his soul, and they never fall short of their duty. (Quran 6:16)
Some Angels are assigned to control the rains, vegetation and provisions by Allah's permission.
And by those Angels who arrange to do the Commands of their Lord (Quran 79:5)
And those who distribute (provisions of rain and other blessings) by (Allah's) Command (Quran 51:4)
Some Angels are assigned to carry out tasks in Heaven and others in Hell.
And the Trumpet will be blown... (Quran 39:68)
And eight Angels will, that Day, bear the Throne of your Lord above them. (Quran 69:17)
And they (inhabitants of Hell) will cry: "O Maalik (i.e. the Angel supervising Hell)! Let your Lord make an end to us." He will say: "(Nay!) Verily, you shall abide (herein) forever." (Quran 43:77)