Who are the mexica or Aztecs?

First of all the mexica and the Aztecs are the same people. The Aztecs were fierce warriors and some people thought the were crude barbarians But they later got rid of that image and where known as civil people. Their empire held about 15 million people and 300,00 alone in their capital the Tenochtitlan. Tenochtitlan was made of lots of little islands and causeways it was a city of wonder and beauty.