Volley gun
The Ribauldequin was a medieval version of the volley gun. It had its barrels set up in parallel. This early version was first employed during the Hundred Years' War by the army of Edward III of England, in 1339. Later on, the late Swiss army employed it.
Arquebus
The development of volley fire – by the Ottomans, the Chinese, the Japanese, and the Dutch – made the arquebus more feasible for widespread adoption by the military. The volley fire technique transformed soldiers carrying firearms into organized firing squads with each row of soldiers firing in turn and reloading in a systematic fashion. Volley fire was implemented with cannons as early as 1388 by Ming artillerists, but volley fire with matchlocks was not implemented until 1526 when the Ottoman Janissaries utilized it during the Battle of Mohács. The matchlock volley fire technique was next seen in mid 16th century China as pioneered by Qi Jiguang and in late 16th century Japan. Qi Jiguang elaborates on his volley fire technique in the "Jixiao Xinshu":