how historians use primary sources to study the past. Today, many records of our lives can only be found online. Those records, however, can be lost if their creators choose to delete them. Do we have an obligation to future generations to preserve our online records? If so, how do we balance the preservation of online content with our own right to privacy in the present? If you think we don’t have this obligation, why not?

tenochtitlan (also spelled tenochtitlán), located on an island near the western shore of lake texcoco in central mexico, was the capital city and religious centre of the aztec civilization. the traditional founding date of the city was 1345 ce and it remained the most important aztec centre until its destruction at the hands of the conquering spanish led by hernán cortés in 1521 ce, which led to the final collapse of the aztec empire.

the muslim brotherhood