How does distributed computing help to create a system faster than the world's fastest computer?

Answer 1

For some specific tasks, splitting it into many small parts and send them to be executed each by a different computer can take advantage of a lot of existing computer and make the problem resolution easier.

Say you take the seti project as an example. It's goal is to analyze radio wave coming from the sky to try to identify artificial patterns. It's a repetitive task, you do the exact same thing for every second of recording for every listening station out there. Instead of having one giant computer that need to process them all at an incredible speed, for a incredible price; they just send tiny pieces of the cake to any volunteer pc over the world and collect the results. It cost nothing, and those computers get automatically updated by their owner every couple of years. There is many thousands of users sharing their pc free time to work on this project, making their combined power quite impressive, and beating any super computer that would like to take them on.

Obviously, not every task is suitable for this. It need to be splitted in a multitude of subtask independant of eadh other to be possible.

As some say, where it take nine month to a woman to give birth, nine women cannot give birth to a child in one month... :-)