The Aztec /ˈæztɛk/ people were certain ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl language and who dominated large parts of Mesoamerica from the 14th to 16th centuries. The Nahuatl words aztecatl [as'tekat͡ɬ] (singular) and aztecah [as'tekaʔ] (plural) mean "people from Aztlan", a mythological place for the Nahuatl-speaking culture of the time, and later adopted as the word to define the Mexica people. Often the term "Aztec" refers exclusively to the Mexica people of Tenochtitlan (now the location of Mexico City), situated on an island in Lake Texcoco, who referred to themselves as Mexica Tenochca [me'ʃika te'not͡ʃka] or Cōlhuah Mexica [koːlwaʔ me'ʃika].
Sometimes the term also includes the inhabitants of Tenochtitlan's two principal allied city-states, the Acolhuas of Texcoco and the Tepanecs of Tlacopan, who together with the Mexica formed the Aztec Triple Alliance which controlled what is often known as "the Aztec Empire". In other contexts, Aztec may refer to all the various city states and their peoples, who shared large parts of their ethnic history and cultural traits with the Mexica, Acolhua and Tepanecs, and who often also used the Nahuatl language as a lingua franca. In this meaning it is possible to talk about an Aztec civilization including all the particular cultural patterns common for most of the peoples inhabiting Central Mexico in the late postclassic period.
Aztec codices (Nahuatl: Mēxihcatl āmoxtli [meː'ʃiʔkatɬ aː'moʃtɬi] ( listen)) are books written by pre-Columbian and colonial-era Aztecs. These codices provide some of the best primary sources for Aztec culture. The pre-Columbian codices differ from European codices in that they are largely pictorial; they were not meant to symbolize spoken or written narratives. The colonial era codices not only contain Aztec pictograms, but also Classical Nahuatl (in the Latin alphabet), Spanish, and occasionally Latin.
Although there are very few surviving pre-conquest codices, the tlacuilo (codex painter) tradition endured the transition to colonial culture; scholars now have access to a body of around 500 colonial-era codices.