Supercomputers are very expensive and are employed for specialized applications that require immense amounts of mathematical calculations. For example, weather forecasting requires a supercomputer. Other uses of supercomputers include animated graphics, fluid dynamic calculations, nuclear energy research, and petroleum exploration.
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.
means a computer (or multiple linked computers) intended on computing massive amounts of
data for projects like mapping the human genome and other science stuff of that scale.
Advantages: Speed, amount of things that can run at once without it slowing down, better graphics capabilities for gaming and graphics designing, and smoother performance.
Disadvantages: Power usage, heat, cost and in the case of overclocked computers heat that leads to damage to the components which in turn will raise the cost through replacement parts. In the case of 64 bit processors, (which can provide better processing capabilities) there can be the downside of compatibility issues for some software.
If you want a really, really fast computer, there are all kind of ways to build the hardware architecture, but one thing that almost all of them have in common is that they run Linux. The top spot now appears to belong to the Tianhe-1A , which means "Milky Way," at a research center at the National University of Defense Technology (NUDT) in Tianjin, China.
How much faster?
NUDT claims the machine is 1.4 times faster than Cray XT5 Jaguar. NUDT claims that the computer's peak performance can hit 1.206 petaflops and jogs along at 563.1 teraflops. To do this, the Tianhe-1A system covers a square kilometer, weights in at 155-tons and uses 14,336 Intel Xeon CPUs and 7,168 Nvidia Tesla GPUs.
The software behind it?
Linux of course. Linux has long been the operating system of choice for the world's fastest computers. While NUDT hasn't said which specific Linux they used, I strongly suspect it's a high-speed optimized version of China's Red Flag Software's Red Flag Linux.
It's not just supercomputers that have become Linux fans. Other high-speed, no-room-for-failure systems have moved to Linux. Many of the world's stock exchanges, where every millisecond counts, have either already switched to Linux or are planning on it.
The bottom line: when speed and reliability is what you have to have, Linux is the operating system you have to use.