In each case, the bonus is a payment to the player that is contingent on the player signing a new contract (Signing Bonus) or remaining with the team (Option Bonus or Roster Bonus). For the player, it really isn’t that important from his perspective what type of bonus it is, because he’s getting paid the amount, regardless of what it’s called. From the perspective of the Salary Cap, the type of bonus is important because of the way that is counts against the Salary Cap.
Roster Bonuses count fully in the year in which they are paid.
Signing Bonuses and Option Bonuses are prorated over the length of the player’s contract (or the remaining years of the players contract, in the case of an Option Bonus), up to a CBA-mandated maximum of 5 years.