Slitherine

Can any one describe the differences between defensive and offensive spears?
Ive seen them described in the manual but cant recall any units in game that have that characteristic/weapon
What types of troops would be be considered "defensive spears"?

None of the armies that are currently in the game use defensive spears. It is part of the game mechanics for when they add new armies that do use them and they are also there for your own scenerio creations so that you can add troops armed in this manner. Defensive spearmen get their bonus when recieving a charge like real ones did who were set to recieve a charge from cavalry. Others are offensive spearmen that recieve their bonus when they charge such as hopolites.