No image of The Middle Ages can be maintained without that of The Jester. Their exact origins areally unknown, but examples go back many Centuries prior to The Middle Ages in some form and in most Cultures. During The Medieval Era, they are seen as early as the 10th Century. Much by way of Historical "inaccuracies" have been out forth regarding just was a Jester (or "Jestering"), was.
Many cite that they were often deformed Humans, or those who suffered from some mental defeat. These Classes were often ridiculed by "normal" and Wealthier Classes. In reality, a Jester was a talented performer who not only told humerous stories and jokes, put could juggle, do Acrobatics etc. In many ways they were akin to a Minstrel Performer.
Their employment was mainly through Royal Patronage. Kings and Queens used them to provide entertainment to both their Family and Guests. "Room and Board" were their payment. He also delivered messages and important letters from Royalty.
The most important facet of The Jester was his appearance. Jesters wore Clothing either too tight or too loose to enhance their comical appearence. They also sewed Belts to their clothes or wore them on their wrists and ankles. This was seen as comical. Another important "Badge of Office", was his Cap or Hat. The Jester Hat was a close fitting Skull Cap without a brim. The top featured a series of cloth extensions which hung down over The Jesters face. These too were covered in Bells.
It is unclear why Red was a primary colors of a Jester. Perhaps it was for him to "stand out" or "be seen", during his performance. By the 15th Century, Jesters were actually licensed *and wore a small wooden "Permit Stamp". Also known as "Fools" and "Jokers", they would slowly fade from use by the 17th Century. However, variants of The Jester are sern on Theatrical Stage, with the introduction of the "Harlequin". The Jester is the direct lineage of today's Comedic Performers.