Von U.S. Navy - http://www.navy.mil/view_image.asp?id=54942 (direct link), Gemeinfrei, https://commons.wikimedia.org/w/index.php?curid=3487832
Railguns are the newest generation of weapon technology. With an electromagnetic field propulsing a ferromagnetic projectile, instead of the normal method using a propelling charge, they can reach speeds up to 9100 km/h or in other words Mach 8,5. They can cover a distance of up to 350 Kilometers while having a potential energy of 25 Megajoule upon Impact and can still penetrate armor plates with 30 centimeters in diameter. With these stats and features it outclasses every other type of ballistic, non-rocket weaponry and could be used for all defensive or offensive cases and even for planetary defense from asteroids.