The HITAC S-820 is a vector

Vector processor

A vector processor, or array processor, is a central processing unit that implements an instruction set containing instructions that operate on one-dimensional arrays of data called vectors. This is in contrast to a scalar processor, whose instructions operate on single data items...

 supercomputer

Supercomputer

A supercomputer is a computer at the frontline of current processing capacity, particularly speed of calculation.Supercomputers are used for highly calculation-intensive tasks such as problems including quantum physics, weather forecasting, climate research, molecular modeling A supercomputer is a...

 developed, manufactured and marketed by Hitachi

Hitachi

Hitachi is a multinational corporation specializing in high-technology.Hitachi may also refer to:*Hitachi, Ibaraki, Japan*Hitachi province, former province of Japan*Prince Hitachi and Princess Hitachi, members of the Japanese imperial family...

. Announced in July 1987, it was Hitachi's second supercomputer, succeeding the HITAC S-810

HITAC S-810

The HITAC S-810 is a vector supercomputer developed, manufactured and marketed by Hitachi. The first models, the S-810/10 and S-810/20, were announced in August 1982, making the S-810 was the second of the first three Japanese supercomputers, following the Fujitsu VP-200, which was announced July...

. The S-820 is categorized as a second generation Japanese supercomputer.

There were five models. The first two, the mid-range S-820/60 with a peak performance of 1.5 GFLOPS and the top-end S-820/80 with a peak performance of 3.0 GFLOPS, were announced in July 1987. These two models differ in the number of vector pipelines installed. In May 1988, the S-820/20 and S-820/40 were announced, followed by the S-820/15 in November 1989.