The Nahuas ( NAH-wahz) are a group of the indigenous people of Mexico, El Salvador, Guatemala, Honduras, Nicaragua, and Costa Rica. They comprise the largest indigenous group in Mexico and second largest in El Salvador. They are a Mesoamerican ethnicity. The Mexica (Aztecs) were of Nahua ethnicity, and the Toltecs are often thought to have been as well, though in the pre-Columbian period Nahuas were subdivided into many groups that did not necessarily share a common identity. Their Nahuan languages, or Nahuatl, consist of many variants, several of which are mutually unintelligible. About 1.5 million...

Chalking the door is a Christian Epiphanytide tradition used to bless one's home, which originated in medieval Europe. == Epiphany == Either on Twelfth Night (5 January), the twelfth day of Christmastide and eve of the feast of the Epiphany, or on Epiphany Day (6 January) itself, many Christians (including Anglicans, Episcopalians, Lutherans, Methodists, Presbyterians and Roman Catholics, among others) write on their doors or lintels with chalk in a pattern such as "20 ✝ C ✝ M ✝ B ✝ 24". The numbers in this example refer to the calendar year 2024 and the crosses to Christ. The letters C, M, and...

David L. Mills (June 3, 1938 – January 17, 2024) was an American computer engineer, Internet pioneer, and professor emeritus at the University of Delaware. He is known for designing the Network Time Protocol. == Education == Mills earned his PhD in Computer and Communication Sciences from the University of Michigan in 1971. While at Michigan, he worked on the ARPA-sponsored Conversational Use of Computers (CONCOMP) project and developed DEC PDP-8-based hardware and software to allow terminals to be connected over phone lines to an IBM 360 mainframe. == Career == In 1977, Mills began working at...