The Black Death, known now as the bubonic plague, was an epidemic several times during the 14th century, but when it is spoken of in history books, the term usually means the plague which killed more than a quarter of the world's population between 1348 and 1350, as that was the outbreak which changed the course of history in England, and set things in motion for the Peasants Revolt of 1381.
 
 
Recommended Resources
The prestigious British Broadcasting Corp. lays out its account and analysis of the Plague, known in the Middle Ages as the "Black Death." It delves into how it came to Europe, how it spread, and what happened when it hit London, Scotland, Wales, and Ireland.
http://www.bbc.co.uk/history/british/middle_ages/black_01.shtml
Shares information about the Plague of 1345 through 1350, including its causes, effects, and contemporary perspectives on the event.
http://www.brown.edu/Departments/Italian_Studies/dweb/plague/
The Black Death and the Jews 1348-1349 CE
Presents an account which goes into detail about the Black Death and specifically about the devastation of the Jewish community in Strasbourg after the panicked residents overthrew nobles.
http://www.fordham.edu/halsall/jewish/1348-jewsblackdeath.asp
Provides an account of the plague which wiped out close to half of Europe's population between 1348 and 1351. It also contains a map of the route that the disease took in order to spread throughout Europe.
http://www.eyewitnesstohistory.com/plague.htm
The Middle Ages: The Black Death
Offers details about the Plague of the Middle Ages, beginning with its arrival in the west, the various different forms of the disease, medical measures, and the Flagellants and their part in the situation.
http://www.boisestate.edu/courses/westciv/plague/