50 Hz

Left over from British Imperialism.

Cloned from the UK's 50Hz.

Ok, Where did they found it?

It seemed like a good idea. Note that the UK's grid is connected to France's 50Hz grid via a subsea DC link, as the two countries' grids are not synchronised with each other.

Parts of the Swiss rail network work(ed) on 16²/₃Hz. 'Why' is a good question.

Why the americas went for 60Hz instead is an equally valid question.

Why it matters is another good question.

The choice of frequency in a 50 to 60 Hz range is to provide less light flickering with low impedance losses.

Why the division between between the two locals

http://in.answers.yahoo.com/question/index?qid=20090415043322AApyBbW

The French King had a pump that had to run at 3000 RPM

The English saw it over the channel

and the Americans always want to be faster, bigger better.

and the poor SA and India have to live with it forever.

In the small Karroo town of Carnavon they used to do 55Hz to be sure the customer at least get 50Hz.

its good for contacting aliens

There is no good single reason why 50 and 60Hz was selected in the 2 parts of the world. At the outset of electrification, every producer had their own ideas about what was the best CPS to use. 16-2/3, 25, 33-1/3, 40, 42, 50, 55, 60 were all common at one time. But as electrification spread and more people wanted to use electricity, equipment had to be made to use it, and equipment mfrs were not going to make a lot of different versions for each system. So at some point or another, Europeans settled on 50Hz and Americans settled on 60Hz, pretty much by accident. England didn't standardize until after WWII, but once their mfrs started exporting electrical equipment, i.e. motors etc., to colonies such as India, whatever they sent is what Indian power companies had to accommodate. And so it went for all of the colonial nations. Japan got pretty well hosed up because they had been 50Hz before WWII, but the American presence after the war brought in a lot of 60Hz equipment. So to this day, they have both!