The Umrah or (Arabic: عمرة ) is a pilgrimage to Mecca performed by Muslims that can be undertaken at any time of the year. It is sometimes called the 'minor pilgrimage' or 'lesser pilgrimage', the Hajj being the 'major' pilgrimage and which is compulsory for every able-bodied Muslim who can afford it. According to some schools of Islamic thought, the Umrah is not compulsory but highly recommended.
Umrah rituals-The pilgrim (mu'tamir), sometimes referred to as a 'Hajji', performs a series of ritual acts symbolic of the lives of the prophet Abraham (Ibrahim) and his wife Hagar (Hajarah), and of solidarity with Muslims worldwide. These acts of faith are:

• Perform a tawaf, which consists of circling the Kaaba four times at a hurried pace, followed by three times, more closely, at a leisurely pace, in a counter-clockwise direction.
• Perform a sa'y, which means rapidly walking seven times back and forth between the hills of Safa and Marwah. This is a re-enactment of Hagar's frantic search for water, before the Zamzam Well was revealed to her by Allah.
• Perform a halq or taqsir, meaning a cutting of the hair. A taqsir is a partial shortening of the hair, whereas a halq is a complete shave of the head.

These rituals complete the Umrah, and the pilgrim can choose to go out of ihram. Although not a part of the ritual, most pilgrims drink water from the Well of Zamzam.
The Umrah can be completed in one hour during the off-peak pilgrimage season. The peak times of pilgrimage are the days before, during and after the Hajj and during the last ten days of Ramadan.
Types of Umrah-There are two types of Umrah, depending on whether one wishes to combine the Umrah with Hajj: al-Umrat al-mufradah al-mustaqillah 'an al-Hajj (al-Umrat al mufradah) and al-Umrat al-mundammah ila al-Hajj (Umrat al-tammatu).
al-Umrat al mufradah refers to Umrah that is performed independently of Hajj.
Umrat al-tammatu refers to Umrah that is performed in conjunction with Hajj. More precisely, the rituals of the Umrah are performed first and then the Hajj rituals are performed.

Scholarly opinions on the Umrah

According to the Hanafi and Maliki madhabs, Umrah is not obligatory, but a highly recommended sunnah (sunnah mu'akkadah). According to the Hanbali and Shafi'i schools (and most Imamiyyah legists), it is obligatory for one who is mustati (one who has the means of performing the pilgrimage) and mustahabb (desirable) for one who is not mustati.
The Imamiyyah school also recognises the obligation of the pilgrim to perform a second tawaf (tawaf al-nisa) in al-Umrat al-mufradah, but not in Umrat al-tammatu.