A supercomputer is a computer with a high performance level compared to a general-purpose computer. The performance of a supercomputer is usually measured in floating point operations per second (FLOPS) rather than million instructions per second (MIPS). As of 2017 there are supercomputers capable of performing over 10 17 FLOPS (one hundred quadrillion FLOPS, 100 petaFLOPS, or 100 PFLOPS).

For comparison, a desktop computer has performance in the hundreds of gigaFLOPS to tens of teraFLOPS.

As of November 2017, all 500 of the world's fastest supercomputers are running Linux-based operating systems. Additional research is being conducted in the United States, European Union, Taiwan, Japan and China to create faster, more powerful and technologically superior exascale supercomputers.

Supercomputers play an important role in the field of computational science and are used for a wide variety of computationally intensive tasks in a variety of fields, including quantum mechanics, weather forecasting, climate research, oil and gas exploration, molecular modeling (computation of structures and properties). chemical compounds, biological macromolecules, polymers, and crystals) and physical simulations (such as simulations of the earliest moments of the universe, aircraft and spacecraft aerodynamics, nuclear weapons detonation, and nuclear fusion). They were very important in the field of cryptanalysis