Norse and Scandinavian sagas can be placed into one of several different categories. There were the king’s sagas, contemporary sagas, chivalric sagas, Icelander’s sagas, sagas of the Greenlanders, short tales of the Icelanders, and legendary sagas.
Some of these classifications resemble modern categorizations of periodical literature.
The king’s sagas are accounts of the lives of Norwegian kings. They are the primary sources of written history for Norway before the 13th century.
Contemporary sagas were written in Iceland during the 12th and 13th centuries. They were written very soon after the events they describe to try and preserve an accurate account of the event, much like a modern news report.
Chivalric sagas are, rather surprisingly, stories of romance composed during the 13th century. They are considered inferior to other forms of saga. Perhaps they were a medieval incarnation of Twilight or Fifty Shades of Gray.
Icelander’s sagas were written in the 13th and 14th centuries and are considered some of the most important written records of the lives of Vikings. They mainly describe the lives of common people and their struggles around the year 1000 A.D. Many of these sagas can be read here.
Short tales of the Icelanders are basically shortened versions of Icelander’s sagas.
Finally, there are legendary sagas. These are perhaps what come to mind when most people think of the word saga. They are very loosely rooted in history and filled with myth and legend, written primarily for the purpose of entertainment rather than historical accuracy. A selection of these Norse tales are available in English here.
Clearly, not all sagas are created equal. They are written in different ways to suit the interests of different readers. Even in an age before the printing press, there was still at least some demand for diversity in literature.