I bet most you people know about the 'Operation Shakti', the second nuclear test by India.
‘Smiling Buddha’ was the name of India's first successful nuclear bomb test on 18 May 1974.
I’ll put up some more lesser known facts in the answer.
Yes,I'm talking about India's second nuclear test.
Most of the nations had conducted Nuclear tests twice but India couldn’t.(Thanks to so called Superpower America who wouldn’t let us conduct it)
Since 1995 India tried had tried twice the testing but India was threatened by the Superpower 'America' of the dire consequences that would follow the tests. Nawaz Sharif sent an international message about possibility of nuclear test by India. This was sent mainly because in all media, BJP announced that making India nuclear is their priority. And that is when America’s CIA spied on India via Satellite.
The technology they used was so advanced that they could even watch the time on the person's wristwatch. India knew about this so we knew that covering up the mission would be harder than the test itself.
Dr. APJ Abdul Kalam was then the DRDO chief and Rajagopala Chidambaram was the Atomic Energy Chief. PM AB Vajpayee held a top secret meeting with the men and other top DAE dignitaries. The meeting was so confidential that even George Fernandes, the then Defence Minister and other ministers of India, were not informed about this.
Just to fool the America's CIA the scientists & engineers working on the project used code words while communicating so that there's no leaking of the words like ‘Taj Mahal’, ‘kumbhakaran’, Sierra’ and ‘White House’
To avoid satellite detection,scientists & engineers used to work at night.
DRDO and Department of Atomic Energy (DAE) scientists would wear army uniforms so that CIA satellite could not figure out the
bombs to be tested in Pokhran(Rajasthan) were brought from Banglore.
Infact even while the preparations the team let the kids play cricket so that it would act as a camaflouge for the plan(Read it in a interview of an scientist who worked there couldn't find any link)
So on the D day 11th May 1998 the test took place. And it was a success.Kalam telephoned Vajpayee. Advani cheered along with Vajpayee and Kalam.
Later Vajpayee announced to the world - "We are now a nuclear weapons country. We have the bomb".
Vajpayee showed no sign of more tests and the world had no idea what would happen and
2 days later India conducted 2 more tests.This test too went unnoticed by America’s satellite.
The DRDO team made us proud,gave a strong impression of what our country can was surely one of the most remarkable event in history of India.