You provide no make nor model, thats all specs.. gotta do better than that.
CMOS = Complementary metal–oxide–semiconductor (aka, Image Sensor)
3MP = 3 MegaPixel Resolution
3.6mm = Camera Optics
2.5" = Sensor Size (assume you meant inches and not feet)
IR = Infrared Lighting
Mini = Small
Camera = Device that captures images