Explanation:

 The appointment of the Judges of the Supreme Court is as per Article 124 of the Constitution. It says that every Judge of the Supreme Court shall be appointed by the President after consultation with such of the Judges of the Supreme Court and of the High Courts in the States as the President may deem necessary for the purpose
In 1993, while deciding a case, the Supreme Court held that as far appointment of judges of Supreme Court and High Courts is concerned, the President shall act in accordance with the opinion of the Chief Justice of India, who will in turn give advice after consulting his colleagues. Up till 1993, the Judges of the Supreme Court were appointed by the President on recommendation of the CJI, but from 1993 onwards, a collegium of 5 senior most judges of Supreme Court judges recommends the names to the law ministry which after scrutinizing send the paper to the president. The government has the option of returning the Collegiums' recommendation once. But in case the collegium sends the same names for the second time, the government is bound to accept them and notify the appointments. This is what has happened recently. The collegium recommended three names. The Government (PMO / Law Ministry) asked the Supreme Court to re-consider the names. The Supreme Court reiterated its recommendations and recommendation goes to Law Ministry and then to the Prime Minister's Office from where it was sent to rastrapati bhavan for final approval