Artillery was classified in various ways including: weight of the projectile, bore diameter, inventor or mobility. Field Artillery was lightweight and mobile. It was able to move with the troops. Besides their mobility the field pieces were further divided into guns and howitzers. Guns had a long range and flat trajectory. Their principle use was to batter heavy constructions with solid shot at long or short range. They were used to destroy parapets, dismount cannon and shoot canister or exploding projectiles, against masses of infantry. The howitzer was highly mobile, it could shoot larger projectiles than the field guns of similar weight. Howitzers would reach targets behind obstructions by high angle firing

Heavy artillery was generally brought to the front to defend or lay siege to an area. The weight of the cannon made it difficult to move with the troops. These pieces were siege guns if used to attack fortifications and garrison guns if used to defend the fortifications. Included in this group are mortars. The heavy guns and mortars could drop shot or shell behind obstructions where troops were located.

The final type of cannon was the stationary gun usually found at fortifications along the seacoast. As the name implies these guns were extremely heavy averaging 50,000 pounds. Their primary targets were naval vessels and landing craft. The largest stationary cannon was a Rodman weighing 117,000 pounds that shot a 1,000 pound projectile 4 1/2 miles.

The cannon during the Civil War was used for more than destruction of enemy lines, it was also a symbol to all on the field. Major Robert Stiles a Confederate artillerist described their role: "The gun is the rallying point of the detachment, its a point of honor, its the flag, its the banner. It is that which men look, by which they stand, with and for which they fight, and for which they fall. As long as the gun is theirs, they are unconquered, victorious; when the gun is last all is lost."

The Civil War was the zenith of the Muzzle-loading cannon. Just as the Civil War marked transitions in military tactics, ammunition, and naval advances, the cannon also evolved. Four major changes occurred in cannon technology: from bronze to steel, from ornate to functional shape, from smoothbore to rifle, and from muzzle-loading to breechloading. These transitions complicate cannon identification. Variations in design, foundries and technological advances produced multiple shapes for cannon with the same name. Examples of shape variations can be seen in the Confederate Napoleon. The five profiles reflect changes made at four different foundries. Adding to the confusion are alterations made by artillery units. At Vicksburg two cannon were modified by their crews, the 32 Pounder Rifled and the 7.5 inch Blakely nicknamed "the Widow Blakely." Despite the confusion over modifications some cannon are recognizable whether they are a 10 Pounder or 100 Pounder, Union or Confederate, an 1861 or 1864 model, these include Parrotts and Dahlgrens. The guns of the Civil War were more than additions to the battlefield, the cannon was a symbol of victory or defeat. The charts represent those guns that aided in the siege and defense of Vicksburg