For the first time since the days of the British Raj, officials in India are to ask people their caste as part of the national census, the biggest of its kind in the world. It is a move that has triggered intense controversy about a painful, vexing subject that the country cannot leave behind.
Having initially chosen not to include caste, the Indian government apparently gave in to demands from opposition parties and decided that, for the first time since 1931, census officials would ask respondents to say what traditional Hindu grouping they belong to.
The decision has sparked fierce debate. Defenders of the move say it will provide up-to-date information about the size and needs of various groups that will be vital for providing grants and reserved jobs and college places for those at the bottom of the caste ladder.
Others are equally adamant that caste should have no place in a country seeking to throw off the shackles of poverty, malnutrition and illiteracy and looking to assume a position as a leading world power.
Among those who have strongly criticised the decision is Amitabh Bachchan, the near-legendary Bollywood actor considered the elder statesman of Hindi movies.
Writing on his blog, Mr Bachchan said that when census officials arrived at his house in Mumbai, he told them that his caste was "Indian".
"My father never believed in caste and neither do any of us," he added. "He married a Sikh, I married a Bengali, my brother a Sindhi, my daughter a Punjabi, my son a Mangalorean... in his autobiography he had [said] future generations of his family should marry into different parts of the country."
In traditional Hinduism there were four main castes and hundreds of sub-groups. In addition there were the "untouchables", who were considered to have no place in society and who are now more usually called Dalits.
For centuries, what job a person did, where they lived, what food they ate and where they were cremated depended largely on their caste. One of those who sought to reform the system was the independence leader Mahatma Gandhi, who, along with social campaigners such as Bhimrao Ramji Ambedkar, argued that caste had no place.
As India has developed, and as more people have moved to the cities, the rigid caste restrictions have loosened slightly. Yet although discrimination on the basis of caste is banned by the constitution, for hundreds of millions of people caste remains a defining, and often debilitating, label. Even now, English-language weekend papers carry pages of adverts for arranged marriages, all categorised under various castes. And a number of online sites cater exclusively to one caste.
Caste also remains hugely important in the world of business and finance. A recent study by the Indian economist Sukhdeo Thorat and Princeton University sociologist Katherine Newman found that having a low-caste surname significantly cut the chances of winning a job interview.
Caste can have deadly repercussions. Parts of northern India are blighted by so-called "honour killings", incidents in which a young woman is murdered by members of her family for having an affair, or eloping, with a man from the "wrong" caste or clan. In one recent high-profile case, police in Jharkhand arrested the mother of a young female journalist, Nirupama Pathak, who was found smothered to death.
The middle-class family, who were opposed to Ms Pathak's planned marriage to a lower-caste man, say she committed suicide. However, her boyfriend claims she was murdered. The young woman's father, a bank manager, told local reporters: "We were trying to convince her to marry within our own caste. That does not mean we killed her."
Despite its purported wish to move away from caste, India has repeatedly opposed including caste in UN guidelines against discrimination. It insists that it is an internal matter for India. At the same time, caste has increasingly become an important means of organising politically.
Kumari Mayawati, the so-called Dalit Queen who heads the Bahujan Samaj Party (BSP), has four times ridden to the position of chief minister of India's most populous state, Uttar Pradesh, with the support of its poorest and most downtrodden people.
Those who want to include caste in the census say the data gathered can be used to help those in need. Writing in the Hindustan Times Sagarika Ghose, a senior broadcaster, said: "The fight against caste is best fought when we know the enemy. Caste is an immutable, invisible and overwhelming reality in our daily lives.
"If we continue to act as if caste does not exist, or deny its existence, we would be failing to do battle with one of the most urgent social inequalities of our time."
Some Dalits fighting for empowerment also believe the information will help, especially if is made publicly available. Pushpa Salaria, head of the Dalit Rights Protection Forum, said: "If we have a census which is centralised then we can have information about weaker sections and minority groups. It will help us know the majority of our country."
India's Caste System
* The caste system has existed for more than 3,000 years in India. In traditional Hinduism, there are four main castes.
* At the top are the Brahmins, the teachers and priests. Next come the Kshatriyas, who are soldiers and administrators. The Vaishyas make up the trading class. The final group is the Sudras, the farming and peasant class.
* In addition there were those considered outside of society and "untouchable" and who are now more usually called Dalits, or in Indian law, "scheduled castes".
* Dalits face routine discrimination with a crime committed against a member of the group every 20 minutes, according to the Dalit Solidarity Network-UK, citing government figures.
* However, the group said this was likely to be a only a fraction of actual incidents since many Dalits did not lodge cases for fear of reprisals.Reuse content