FLOPS means floating point instructions per second -- an approximate measure of a computer's processing speed. A megaflop is one million FLOPS, and a gigaflop in one billion FLOPS. The most powerful supercomputers have speeds measured in teraflops, or units of 1012 FLOPS.
FLOPS are not that useful as a benchmark for modern computers because there are many other factors in computer performance other than raw floating-point computation.
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