From English Wikipedia and Japanese Wikipedia:
Cave Co., Ltd. (Computer Art Visual Entertainment) is a Japanese video game company founded the 15th of june 1994. They are known primarily for their manic shoot'em-ups. Cave remains one of the most active makers of arcade shoot-'em-ups in the Japanese market. The company was formed primarily from the remains of Toaplan, and several of their early games are considered to be spiritual successors to prior Toaplan works, in particular Truxton and Batsugun. Cave currently produces new titles for the arcade and cell phones, as well as online games for PC, such as Megami Tensei Imagine.
Among their titles are (among others):
Dodonpachi /Daioujou /Daifukkatsu
Touge MAX G (racing game)
Mushihimesama (Insect Princess)
Muchi Muchi Pork
Princess Debut (dance action game /Nintendo DS)