The Hulk vessel was invented in the early medieval period - it was a sea craft that is known as the predecessor of the more advanced carrack and carvel vessels.
A Knarr was a vessel used for cargo storage - it was a cargo ship that had a wide hull and was deeper and shorter than the standard longship. The reason for this was for it to store more cargo and for much smaller crews to operate it.
People in the middle ages had it rough, the early medieval period from 5th to 10th century was so messed up that people came up with the term "Dark Ages" but, that did not stop them from enjoying the fun part of life.
According to texts that have come down to us from Alamut, Hassan-i Sabbah liked to call his disciples Asasiyun, meaning people who are faithful to the Asās, meaning "foundation" of the faith.
There were professional spies employed by the kings that were spread everywhere. They didn't have a 007 look to them but they still had a good set of skills.
In this way, jesters also played a role to prevent over-oppression due to political affairs and they also helped the members of the nobility to rule well.
Typography was invented twice: once in China and Korea and in medieval Europe. In China, printing was invented, according to some data (Julien, "Documents...
