Worldwide, Sikhs number more than 23 million, but more than 90% of Sikhs live in the Indian state of Punjab, where they are close to 65% of the population. Large communities of Sikhs live inthe neighbouring states, and large communities of Sikhs can be found across India. However, Sikhs are only about 2% of the Indian population. Migration beginning from the 19th century led to the creation of significant communities in Canada (Brampton & Malton, Ontario; Surrey, British Columbia), the United Kingdom, the Middle East, East Africa, Southeast Asia and more recently, the United States, Western Europe, Australia, and New Zealand.
As with most world religions, there are groups of Sikhs (such as the Namdharis, Ravidasis and Udasis) who do not adhere to the mainstream principles followed by most Sikhs. Some of these groups may not consider themselves a part of Sikhism, although from an outsider's perspective similarities in beliefs and principles may firmly render them a part of the Sikh religious domain. Groups such as the Nirankaris have a history of bad relations with mainstream Sikhism, and are considered pariahs by some Sikhs. Others, such as the Nihangs, tend to have little difference in belief and practice, and are considered Sikhs proper by mainstream Sikhism.
Festivals in Sikhism mostly centre around the lives of the Gurus and Sikh martyrs. The Sri Gurudwara Prabhandak Committee (SGPC), the Sikh organisation in charge of upkeep of the gurdwaras, organises celebrations based on the new Nanakshahi calendar. This calendar is highly controversial among Sikhs and is not universally accepted. Several festivals (Hola Mohalla, Diwali and Guru Nanak's birthday) continue to be celebrated using the Hindu calendar.
Sikh festivals include the following :
Guru Gobind Singh Javanthi : birth of Guru Gobind Singh Ji.
Lohri : is a harvest festival, originally celebrated in Punjab. Although it has nothing to do with the sikh religion but sikhs being the predominant farmers in Punjab makes it look like a Sikh festival. Nowadays it is celebrated more as a tradition than anything else. Any beliefs that Lohri is celebrated only at the birth of a boy is because of the discrimination of women faced in old Hindu soceities, the very thing opposed strongly and outrightly by all Sikh Gurus and other saints like Kabir. Nowadays even at the birth of a daughter some families celebrate Lohri. Lohri would be more correctly termed a Punjabi festival rather than a Sikh festival.
Maghi : commemorates the martyrdom of the "Forty Immortals," forty followers of Guru Gobind Singh who had previously deserted him, fought bravely against overwhelming Mughal army forces and were martyred in Muktsar. Guru Gobind Singh blessed them as having achieved mukti (liberation) and cremated them at Muktsar.On Maghi, Sikhs visit gurdwaras and listen to kirtan (hymns). Naturally, the largest gathering is at Muktsar where an annual fair is held.
Holi/Hola Mohalla : In Punjab it is celebrated at Anandpur Sahib and in other cities such as Ludhiana Hindus and Sikhs celebrate together. In Punjab and other major cities like Mumbai, Delhi, Kolkata, Sikhs and Hindus come together for Hola Mahalla. But again Holi is actually a Hindu festival having no place in Sikhism with Sikh participation limited to Hola Mohalla where sikhs display their martial skills.
Vaisakhi/Baisakhi : is a Hindu and Sikh festival that celbrates the beginning of the harvest season in India. It is also celebrated for the Birth of the Khalsa, or Sikh religion. Vaisakhi is celebrated at a large scale at Harimandar Sahib, Amritsar. In Canada, USA, and other Sikh and Hindu populated areas, South Asians come together for a public mela or parade, and enjoy free food of all sorts of Indian cuisine. The main part of the mela is where a local Sikh Temple ( Gurdwara ) has a beauitful Indian theme float where the Guru Granth Sahib (Sikh Holy Book) is located and everyone must offer their prayers by touching the float.
Martydom of Guru Arjan Dev Sahib rjan Dev Sahib was martyred on this day, according to the Nanakshahi calendar.
Parkash Divas is the day where the Guru Granth Sahib was instituted. Sikhs go to a local temple for a prayer, and hymns.
Diwali/Bandi Chod Divas : On the day of the Hindu festival Diwali, Sikhs celebrate the Bandi Chod Divas. It celebrates the release of Guru Hargobind Singh from Gwalior Fort with him freeing 52 other kings as well. It is celebrated by lightning divas and going to a Gurdwara to listen to gurbani.
Guru Nanak Ji's Jayanthi : On this day Guru Nank was born in Nanakana, a small town in Pakistan. Every year Sikhs go to a Gurdwara and offer their prayers there. Sometimes divas are lit infront of the Gurdwara, in honor of the Guru Jis Birthday.
Martyrdom of Guru Tegh Bahadur Sahib : On this day Guru Tegh Bahadur was martyred when he refused to convert to Islam. On this day Sikhs go to a Gurdwara for a prayer.