26 January is the national holiday in India, celebrated as Republic Day. It marks the day when the Constitution of India came into effect on January 26, 1950, replacing the Government of India Act 1935 as the governing document of India. This day is also celebrated as the anniversary of the Purna Swaraj declaration of independence, made by the Indian National Congress on January 26, 1930.

The main Republic Day celebration is held in the national capital, New Delhi, at the Rajpath before the President of India. On this day, a grand parade is held which is attended by dignitaries from all over the world, along with the general public. The parade starts from the Rashtrapati Bhavan and proceeds towards the India Gate. It is a display of India's cultural and military heritage.

The parade features various floats representing different states of India, showcasing their culture and traditions. The parade also includes a display of tanks, missiles, and other military equipment. The highlight of the parade is the flypast by the Indian Air Force, which includes various aircrafts such as the Sukhoi Su-30, Mirage 2000, and the newly inducted Rafale fighter jets.

The President of India also gives away bravery awards to individuals from various fields, such as the military, police, and civilians, for their outstanding acts of bravery. The parade ends with a display of colourful floats, known as the “Jhanki”, depicting scenes from Indian mythology and folktales.

The celebration of Republic Day is not limited to the national capital, as it is also celebrated with great enthusiasm in all the states and Union Territories of India. Each state has its own unique way of celebrating the day, but all of them include a parade and a display of cultural performances.

The day is also celebrated in Indian embassies and consulates around the world, where the Indian tricolour is hoisted, and the national anthem is played. This is followed by cultural programmes showcasing the rich cultural heritage of India.

Apart from the grand parade and cultural performances, the day is also celebrated in schools and colleges across the country. Students participate in various patriotic activities, such as flag hoisting, cultural performances, and essay writing competitions. This helps to instill a sense of national pride and unity among the youth.

In conclusion, 26 January is an important day in the history of India, as it marks the adoption of the Constitution of India and the declaration of Purna Swaraj. It is a day to celebrate the diversity and unity of the country, and to remember the sacrifices of those who fought for India's freedom. The grand parade and cultural performances serve as a reminder of India's rich cultural heritage, and the celebrations in schools and colleges help to instill a sense of national pride and unity among the youth.