The word 'secular' refers to things which are not religious or spiritual. The concept of 'secular' in fact was first used in Europe where the church had complete control over all types of properties and nobody could use property without the consent of the church. Some intellectuals raised their voice against this practice. These people came to be known as 'secular' which mean "separate from church" or "against church". In India, this term was used in a different context after independence. 
After the partition of the country, the politicians wanted to assure the minority communities, particularly the Muslims, that they would not be discriminated against in any way. Hence, the new Constitution provided that India would remain 'secular' in the Constitution, which meant that: (a) each citizen would be guaranteed full freedom practise and preach his religion, (b) state will have no religion, and (c) citizens, irrespective of their religious faith, will be equal. In this way, even the agnostics were given the same rights as believers. This indicates that a secular state or society is not an irreligious society. Religions exist, their follower continue to believe in and practise the religious principles enshrined in their holy books, and no outside agency, including the state, interferes in the legitimate religious affairs.
two important ingredients of a secular society are:
(a) complete separation of state and religion
(b) full liberty for the followers of all religions as well as atheists and agnostics to follow their respective faiths.
In a secular society, the leaders and followers of various religious communities are expected not to use their religion for political purposes. However, in practice, Hindu, Muslim, Sikh and other religious communities do use religion for political goals. Each political party labels other political parties as non-secular.
After the demolition of Babri Masjid structure at Ayodhya in December 1992, a case (popularly called S.R. Bommai case) was filed in a court for the dismissal of the state governments run by the Bharatiya Janata Party (BJP). The judges constituting the nine-judge bench dwelt upon the term 'secularism' and averred that though the term was embedded in the Constitution it was wisely left undefined because it was not capable of any precise definition. Secularism in the Constitution guaranteed equal treatment to all religions, and state governments were to regulate the law in order to enforce secularism. As such, on legal consideration the plea for dismissal of BJP governments was not accepted. No wonder, some people say that S.R. Bommai's case in the Supreme Court was just ganging up against one political party (BJP). In a another case involving the Chief Minister of Maharashtra,
the Supreme Court had held that an appeal to Hindutva was permissible under the Representation of the People Act. What was banned was the criticism of the other party's religion. It may thus be said that secularism for political parties has implied the creation of a vote bank comprising Muslims and the scheduled castes and scheduled tribes. In the elections for the Lok Sabha in May 1996 and for Uttar Pradesh Vidhan Sabha in October 1996, when the BJP emerged as the largest single party at the centre as well as in Uttar Pradesh, political parties with vested interests joined together in describing the BJP as a communal party. The cry against communalism was raised only to seek votes and attain political power. A coalition of 13 parties at the Centre (in June 1996) was based not on any common acceptable minimum programme but only on one and programme of preventing a so-called 'Hindu party' from forming a government. 
Communalism, thus, is neither a political philosophy nor an ideology nor a principle. It came to be imposed on the Indian society with a political objective. The communal-secular card is now being played for political motives only. The bogey of communalism is being kept alive not for checking ditional disintegration but with a view that minority vote bank does not desipate itself into the larger Indian ethos. Even those political leaders who are too corrupt and who extensively practise casteism accuse political leaders of opposite parties for being communal. The power seekers thus use secularism as a shield to hide their sins, thereby ensuring that people remain polarized on the basis of religion and India remains communalized.
Secularism in India