The Five Pillars of Islam are obligatory activities that all Muslims are expected to perform. They include a sincere profession of faith, the performing of ritualistic prayers five times a day, the giving of alms to benefit the poor, and a period of fasting for a month during Ramadan. The fifth pillar is the Hajj, or pilgrimage; if they are financially and physically able, at least once in their lifetime every Muslim is required to journey to Mecca on the last month of the Islamic calendar and undertake a series of rituals. If the Hajj journey would place too much hardship on a pilgrim's family, that pilgrim is allowed to appoint a relative or friend as a substitute or stand-in.
Before they approach the holy places, pilgrims change their apparel into special clothes known as ihram garments. Men wear two white sheets wrapped around their bodies, and women wear simple versions of their normal clothes with white head coverings. Pilgrims avoid cutting their nails or hair during Hajj. Once they enter Mecca, pilgrims walk seven times around the Ka'ba, kiss a black stone, run seven times between two hills, visit certain holy places, sacrifice an animal, and throw stones at pillars representing the Devil and his demons. Men usually have their heads shaved, and women remove a lock of hair.
There are several reasons why Muslims make pilgrimages to Mecca to perform Hajj. First of all, as mentioned above, it is one of the five obligatory tenets of the faith. Muslims express their devotion to God by performing this pilgrimage. Their journey replicates that of the Prophet Muhammad.
Hajj is also a manifestation of unity among Muslims. During Hajj, all Muslims are equal regardless of their nationality, race, color, culture, economic status, or social status. Divesting themselves of their individual garments and adornments and putting on the simple ihram clothes is an expression of equality. This equality of status and purpose also brings on a feeling of humility and tranquility.
Finally, pilgrims who properly perform Hajj are cleansed of past sins and able to make fresh starts. After believers successfully undertake Hajj, they are able to add the honorific Hajji or Hajjiyyah to their names.