The Khalsa

The Khalsa began when Guru Gobind Singh, holding a sword, asked a crowd of Sikhs which ones would die for their faith and for them to step into a tent. One man walked into the tent and the Guru followed. A few seconds later only the Guru emerged holding his sword, covered in blood. After asking if there were any more, four people strode into the tent, ready to be slaughtered for their faith. It was then that the crowd found out that none of the five men were actually killed, and these five men became The Khalsa Brotherhood. They were baptised and they could then baptise others that follow the "Five Ks" and the other requirements into the brotherhood.

The Khalsa baptism ceremony involves drinking of Amrit (sugar water stirred with a dagger) in the presence of 5 Khalsa Sikhs as well as the Guru Granth Sahib. The initiate is instructed in the following; (a) You shall never remove any hair from any part of thy body, (b) You shall not use tobacco, alcohol or any other intoxicants, (c) You shall not eat the meat of an animal slaughtered the Muslim way, (d) You shall not commit adultery. The initiate is required to wear the physical symbols of a Khalsa at all times as well as follow the Khalsa Code of Conduct.

The 5 K's

The Khalsa must carry the five symbols, Panj Kakka, or the Five Ks:

1. Kesh – uncut hair to represent the natural appearance of sainthood. It is argued by some that the requirement is Keski instead, a small turban to be worn underneath a bigger turban. However the latter idea is not contradictory to the former, since the purpose of the Keski is to preserve the kesh.
2. Kanga – a small comb.
3. Kaccha – warrior short trousers, also denotes chastity.
4. Kara – steel bangle as a sign of restraint and bondage, and a symbol of dedication to the Guru. Guru Gobind Singh proclaimed that by wearing Kara all fears will be removed.
5. Kirpan – a sword for defence. The Kirpan is a symbol of dignity, power and courage. Kirpan is from Kirpa (act of kindness, Sanskrit) + Aan (self respect, Persian).

He is to lead his life according to the Guru's teaching and repudiate non-Sikh rites and ceremonies. This includes abandoning the caste system. All Sikhs were taught to treat all in the community as equals; no distinction was made to be between the different professions.

"He who keeps alight the unquenchable torch of truth, and never swerves from the thought of One God; he who has full love and confidence in God and does not put his faith, even by mistake, in fasting or the graves of Muslim saints, Hindu crematoriums, or Jogis places of sepulchre; he who recognises the One God and no pilgrimages, alms-giving, non-destruction of life, penances, or austerities; and in whose heart the light of the Perfect One shines, - he is to be recognised as a pure member of the Khalsa" (Guru Gobind Singh, 33 Swaiyyas)

Source - http://en.wikipedia.org/wiki/Khalsa