The United States was plagued by another rogue gunman yesterday as the recently identified Wade Michael Phillips went on a shooting spree in a Wisconsin Sikh Temple. The tragedy comes less than a month after the notorious Aurora, CO shooting at the hands of James Holmes, where he killed 12 innocent moviegoers during a midnight showing of The Dark Knight Rises. Phillips, who by many accounts was connected to white supremacy groups and materials, killed 6 and wounded 3 including a police officer who was shot 8 or 9 times in the face and extremities. Phillips was shot and killed by police. With a name and a face already attached to the suspect, one of the remaining burning questions many are surely asking is, “What exactly is a Sikh?” To help you better understand the religion in question, here’s a little bit of background on what a Sikh is and the definition of Sikhism.

What Is a Sikh, and What is Sikhism?

A Sikh is a follower of Sikhism (Sikh is Punjabi for “disciple”), a religion founded in the Punjab region of Asia–an area straddling the border between Pakistan and India. Sikhism is a monotheistic religion that preaches a message of devotion and remembrance of God at all times, truthful living, equality of mankind and denounces superstitions and blind rituals.

Where and how did Sikhism come about?

The religion’s founder, Guru Nanak (pictured), was born in 1469. Credited with having an intellectual curiosity and binding faith, Guru Nanak was born into a Hindu family but rarely practiced and often mediated by himself. As the story goes, at the age of 30 Guru Nanak went missing for an extended period of time but upon his return, he stated “There is no Hindu, there is no Muslim.” It is widely accepted by Sikhs that this was the moment that Nanak began to spread the teachings of what was then the beginning of Sikhism. The authority figures in the religion are the 10 Gurus (the last guru died in 1708) and the Sri Guru Granth Sahib, a collection of the poetry of the Gurus and the writings of saints of other faiths whose thoughts were consistent with those of the Sikh Gurus.

What do they believe?

At their most basic, the Sikh principles are service, humility, and equality. Sikhism advocates the pursuit of salvation in a social context through the congregational practice meditation on the name and message of God. They follow the teachings of the Gurus and the writings in the Sri Guru Granth Sahib. They don’t focus on one’s soul ending up in a Heaven or Hell-type realm, but more on reaching salvation. They worship in a Gurdwara (what other religions would call a temple or church) and each Gurdwara contains a free community kitchen for all peoples of all faiths.

Sikhs in the U.S.

Sikhism is the 5th largest religion in the world with 19 million practicing Sikhs. The United States estimates there are roughly 250,000 Sikhs within its borders, residing mostly on the East and West coasts and a notable populations in Texas. Notable Sikhs in the United States include: Nikki Haley, Governor of South Carolina; Dalip Singh Saund, former U.S. Representative, first Asian-American and Indian-American member of Congress; Preet Bharara, U.S. Attorney for the Southern District of New York famous for insider trading, financial fraud, and organized crime cases.

The shooting is deemed an “act of domestic terrorism” and the investigation has been taken over by FBI.