The Yazatas appear to occupy precisely the same role in Zoroastrianism as the Devas do in Hinduism.
The Yazatas are divided into male and female, though it is sometimes acknowledged that they are genderless. Many of the Yazatas are mentioned alongside counterparts or partners, some of the opposite gender, and some of the same gender. For example, Ahura is often paired with Mithra, Rashnu is often paired with Sraosha or Arshtat (the feminine angel of rectitude), Armaiti is often paired with Rata (the feminine angel of charity and grace), and Vohu Mana is sometimes paired with Akhshti (the feminine angel of peace). The pairings are not usually said to be of a sexual or marital nature.
The first Yazata, both ontologically and chronologically, is Ahura Mazda. Next are the Ameshaçpentas. For the order and hierarchy of the rest of the Yazatas, we have a medieval text to go by, the Bundahishn. The next creation listed in the Bundahishn after the Ameshaçpentas, Good Speech, is mysterious to me. The next creation was the Yazata of obedience, Sraosha. Sraosha has been identified with the Archangel Gabriel by the great Sufi philosopher Suhrawardi. The next creation after Good Speech and Sraosha was Manthra Spenta (Holy Words/Scriptures). The next creation was Nairyosangha the Archangel of Messengership. After creating Good Speech, Sraosha, Manthra Spenta, and Nairyosangha, the next creation was Rathwo Berezato, the Yazata of the six divisions of the year. Then came Rashnu the Yazata of Truth and Justice, and Mithra the Yazata of Covenants and Oaths. These two, along with Sraosha, are the Yazatas through whom men will be judged on Judgment Day. The last spiritual creations listed are Ard the Yazata of Blessings, and several angels corresponding to specific blessings.
It seems worth mentioning that the various parts of the Avesta are said to literally be Yazatas.