Changes

Navigation played a critical role not just in trade but also in warfare and the spreading of ideas, diseases, migrations, and even technologies that accelerated cultural change. Navigation increasingly made movement by sea easier over time; however, much of this knowledge that facilitated movement was accumulated knowledge that took many centuries or even millennia to develop. However, once knowledge, particularly in astronomy, reached a critical threshold of knowledge, we do begin to see more rapid developments made, where navigation became easier and technologies (e.g., the astrolabe) began to be developed to facilitate use of this knowledge.

==Classical Developments==

By the late first millennium BC, new developments facilitated further navigation capabilities. This included the development of navigational charts and information passed down to sailors. These charts include types of notes and descriptions that likely assisted sailors over generations.<ref> For information on Classical navigation charts, see: Major, F. G. 2013. Quo Vadis: Evolution of Modern Navigation. New York: Springer, pg. 298.</ref> The Antikythera mechanism, found in 1900 near the Greek island of Antikythera, was a mechanical device with gears and wheels that seems to have been used to aid navigation in the 3rd or 2nd century BC.<ref>For more information on the Antikythera mechanism, see: Stikas, Constantin. 2014. ''Antikythera Mechanism; the Book: Unwinding the History of Science and Technology''.</ref> Mostly likely this device allowed sailors to calibrate the positioning of starts during different times of the year. The device integrates a lot of accumulated knowledge, particularly in astronomy, where sailors could utilize this mechanism for travel and predicting astronomical events such as eclipses. Most likely, the device utilized complex Babylonian-inspired predictions used for astronomical positioning. In effect, the device was a sort of computer that likely helped sailors determine navigation from any given point utilizing astronomical positions. Similar to this, the astrolabe is perhaps the best known device to have been utilized by this time. This device allowed calculations of location to be made based on measuring stars and planets altitude above the horizon.<ref>For more information on the astrolabe, see: Johnson, Donald S., and Juha Nurminen. 2007. ''The History of Seafaring''. London: Conway, pg. 107.</ref>