A class of very powerful computers that have extremely fast processors, currently capable (2018) of performing over 200 petaflops (see flops); all are now created from large numbers of standard microprocessor chips operating in parallel, with core numbers counted in the millions (see also MPP, SMP). Large main-memory capacity and long word lengths are the other main characteristics. Supercomputers are used, for example, in meteorology, engineering, nuclear physics, and astronomy. Several hundred are in operation worldwide at present. Principal developers are the Chinese National University of Defence Technology, Cray Research, Dell, IBM, and Fujitsu.