It could be argued that the use of nuclear power began in the 1950's when a nuclear reactor in the Idaho desert supplied electric power to a local community.
A commercial nuclear power plant
Yes.
The first commercial nuclear power plant in the US was built in 1957 in Shippingport, Pennsylvania. The first commercial nuclear power plant in the world was built in 1956 in Calder Hill, UK.
The USA
4-5%
The majority of commercial nuclear power reactors use uranium (natural or enriched) as nuclear fuel.
For electricity production, 1956
Shippingport nuclear power point: May 1958, the first commercial reactor in USA.
Nuclear fission is used in commercial power generation. We don't use fusion yet in that application because we have not conquered the technological problems in doing so.
India presently has 4.78 GWe of nuclear power capacity. Another 10 GWe or so are in the planning stages for the middle to late part of this decade.
Charles B. Ramsey has written: 'Commercial Nuclear Power' -- subject(s): Safety measures, Nuclear power plants