Experience is a measure of how seasoned a character is. Players have a general experience category that defines their overall level and individual experience for each their skills which defines how proficient they are.
Each party member is given a number of “shares” equal to their character level + 4. If the total number of shares in the party is higher than the experience the monster gives, the experience is not split. If the monster does give enough experience to be split, then that experience is given to the party members based on how many shares they have. For example: Sam and Frodo are in a party together. Sam is level 1, and Frodo is level 6. Sam has 5 shares (level 1 + 4 = 5), and Frodo has 10 (level 6 + 4 = 10). Because Sam has a third of the party's shares (5 of 15), he will get a third of any shared experience. If they kill a monster worth 150 experience, then Sam will get 50 experience, and Frodo will get 100.