In ancient China, there were emperors who ruled over the country. They had wives called imperial consorts who helped take care of the palace. These consorts were ranked based on their importance and how close they were to the emperor.
Just like how we have "levels" of friends, the imperial consorts had different levels too. The highest rank was the Empress, who was the most important and closest to the emperor. Think of her like the emperor's best friend who he trusted the most.
Below the Empress were the Noble Consorts, who were also very important but not as close to the emperor as the Empress. Think of them like really good friends who the emperor trusted and spent time with often.
Next were the Consorts, who were still important but not as much as the Noble Consorts. They were more like friends of friends of the emperor.
The lowest rank was the Imperial Concubine, who was not married to the emperor. She was like an acquaintance who the emperor knew but didn't spend much time with.
Overall, the ranks of imperial consorts showed how important they were to the emperor and how close they were to him. The higher the rank, the more trusted and respected they were in the palace.