Turrets, or automatic assault cannons, is a collective term for a wide range of automatic weapons. What unites these different types of weapons are auto-aim, velocity and heavier forms of ammunition. These types of weapons are often mid to long ranged weapons and can have different uses such as suppressive fire as well as head on assault. However the latter demands a matter of mobility that few suppliers offer, and therefor turrets are generally considered to be defensive weapons. Famous types of turrets are the Stealth and Attack Series (SAS), the Mobile Automatic Artillery-series (MAA) and the Engage and Destroy-series (ED).
Turrets have been used thoroughly throughout history. Perhaps the most famous battle in which turrets played a significant part was the Battle of Santa Marta. The Grand Colombian troops were heavily out-numbered and therefor had to base their whole coastal defense on turrets. Something the NAA and WTMA troops were prepared for, but still lost heavy casualties due to the turrets effectiveness.
Since turrets are mostly fully automatic, there is no person to fully hold responsible for eventual war crimes. This problem has been heavily discussed in international meetings between government officials, but as of yet to no avail.