difference between supercomputers and mainframe?

Answer 1

The distinction between supercomputers and mainframes, generally one can say that supercomputers focus on problems which are limited by calculation speed while mainframes focus on problems which are limited by Input/Output and reliability. As a consequence:
• Supercomputers are optimized for complicated computations that take place largely in memory, while mainframes are optimized for simple computations involving huge amounts of external data accessed from databases ("mixed workload").
• Supercomputers tend to cater to science and the military, while mainframes tend to target business and civilian government applications.
• Supercomputers often run tasks that can tolerate interruption (for example, global warming forecasts and academic research). Mainframes tend to run those functions that must run reliably, even for years of continuous service (for example, airline bookings or credit-card processing).
• Supercomputers are often purpose-built for one or a very few specific institutional tasks. Mainframes typically handle a wide variety of important, everyday tasks. Consequently, most supercomputers are one-off designs, whereas mainframes typically form part of a manufacturer's standard model lineup.
• Mainframes assiduously and thoroughly support older software (dating back to applications written in the mid-1960s, in IBM's case) alongside new software. Supercomputers tend not to have backward compatibility as a central design feature, since backward compatibility usually sacrifices raw performance.
Also:
Supercomputers uses hundreds or thousands of processors (64000+), mainframe up to one hundred.
Supercomputers price is up to hundreds of millions, mainframe a couple of millions.
Supercomputers uses parallel procesing, mainframe multiprocessing.

Answer 2

The chief difference between a supercomputer and a mainframe is that a supercomputer channels all its power into executing a few programs as fast as possible, whereas a mainframe uses its power to execute many programs concurrently.

A supercomputer is a computer that leads the world in terms of processing capacity, particularly speed of calculation, at the time of its introduction. Cray and Tera are supercomputer manufacturers.

A mainframe computer was called that because of their very substantial size and requirements for specialized HVAC and electrical power. Nowadays mainframes support access via any user interface, including the Web. IBM, Tandem, DEC(Digital Equipment Company - now Hewlett Packard) produced mainframe computers - many of which are still in use. An IBM mainframe was the first Web server anywhere outside Europe.