1.VED VYAS

There is no story of the great epic MAHABHARAT without knowing about its creator sage "VED VYAS", the son of Satyavati and one of the most important characters of Mahabharat himself .Satyavati was also the step mother of devavrat or so called "BHISHMA" one of the most famous character of mahabharat , the wife of Shantanu.He is also called as Krishna dvaipayana.Guru purnima is a festival devoted to him Ved vyasa is said to have recited the epic in a single go and was written by Hindu god lord GANESH who was ready to pen it down only if it was recited in a single go. It took him 3 long years to narrate this whole story during which Ganesh raised only to purify hiself during the recitation.It is also believed that along with the mahabharat sage VYASA also recited all 18 PURANAS and all the UPANISHADS known to the world. He is also believed to have divided one single ved into 4 different vedas known to the world now i.e RIG VEDA , SAM VEDA, YAJUR VEDA AND ATHARVA VEDA for their better understanding according to subject it deals with.He was also the biological father of Pandu,the father of pandavas;dhritarashtra,the father of kauravas and wise Vidur,who later became the minister at the royal court of kuru dynasty,the reason being the death of Vichitra-virya leaving the dynasty without a heir.He was asked by his mother to do so as there was no one to ascend the throne after his death and bhishma refusing to do so due to his wow of being brahmachari (unmarried) throughout his life .The whole story being written here is whatever i understand from the reading of the great epic's English translation and hence i would like to hear from the readers anything not up to the mark.This is the story which was narrated by great sage and storyteller Ugrasrava also called as SAUTI who heard it directly from VAISAMPAYANA who was narrating it to JANAMEJAYA, the son of PARIKSHIT,grandson of ABHIMANYU and great grandson of ARJUNA .
You may get more information (if it is available) here
 http://en.wikipedia.org/wiki/Vyasa