The K supercomputer, built by the Fujitsu Company, is as fast as one million desktop computers connected together.
It has more than three times the power than the previous title-holder and is capable of performing eight quadrillion calculations each second.
High-tech: The K supercomputer at Riken's laboratory in Kobe, contains 672 racks with a total of 68,544 CPUs
The previous fastest machine was the Chinese computer Tianhe-1A, which was clocked at 2.507 petaflops and highlighted the emergence of China's growing technological and economic power.
The Tianhe- 1A machine was the first time China had topped the speed list, wrestling the title from the U.S. who had four of the top ten supercomputers.