- Round shot: These were the most common type of cannonball, and consisted of a solid sphere of iron. They were effective at long range and could cause significant damage to ships, fortifications, and troops.
- Explosive shells: These cannonballs were filled with gunpowder and were detonated by a fuse. They were effective at destroying fortifications and clearing trenches, but were less accurate than round shot.
- Shrapnel shells: These cannonballs were filled with metal balls or scraps of iron, which were scattered when the shell exploded. They were effective at killing and wounding troops, but were less effective against fortifications.
The most effective cannonball in the Civil War ultimately depended on the specific circumstances of the engagement. For long-range attacks against ships or fortifications, round shot was the best choice. For close-range attacks against troops, explosive shells or shrapnel shells were more effective.