The tuft of Hair known in India as sikha is a long tuft, or lock of hair left on top or on the back of the shaven head of a male Orthodox Hindu.

Though traditionally all Hindus were required to wear a śikhā, today it is seen mainly among Brahmachari, ‘celibate monks’ and temple priests

The śikhā is tied back or knotted to perform religious rites. Only funerals and death anniversaries are performed with the śikhā untied or with disheveled hair. Disheveled hair is considered inauspicious, and represents times of great sorrow or calamity.

Father of my nation, Mahatma Gandhi felt ashamed to wear the Sikha when he was in England & South Africa,since he could become laughing stock for the funny appearance.

In his autobiography, Mohandas K. Gandhi  writes about his encounter with an orthodox Hindu: In his words…

“He was pained to miss the shikha (tuft of hair) on my head and the sacred thread about my neck and said: ‘It pains me to see you, a believing Hindu, going without a sacred thread and the shikha.

These are the two external symbols of Hinduism and every Hindu ought to wear them.’ … [T]he shikha was considered obligatory by elders. On the eve of my going to England, however, I got rid of the shikha, lest when I was bareheaded it should expose me to ridicule and make me look, as I then thought, a barbarian in the eyes of the Englishmen.

In fact this cowardly feeling carried me so far that in South Africa I got my cousin Chhaganlal Gandhi, who was religiously wearing the shikha, to do away with it. I feared that it might come in the way of his public work and so, even at the risk of paining him, I made him get rid of it”.

The śikhā was one of the few symbols of Hindus that transcended caste, language or regional barriers. Although there were variations of the style of sikha amongst communities, it was obligatory for all males.

Information Courtesy- WIKIPEDIA

I have seen similar but slightly different hairstyles ,Chinese having in some of the Chinese Movies.

History of the Hairs World

In India I have come across Westerners who are followers of ‘ISKCON’ 

(International Society For Krishna Consciousness),having ‘tuft of hair

Why a devotee has a Sikha ?

Any thoughts on Men’s hairstyle in other religions ? Enlighten me further.