Ramadan is a time of spiritual reflection and worship. Muslims are expected to put more effort into following the teachings of Islam and to avoid obscene and irreligious sights and sounds. Sexual intercourse among spouses is allowed after one has ended the daily fast. During fasting intercourse is prohibited as well as eating and drinking, one is also encouraged to resist all temptations while you are fasting. Purity of both thoughts and actions is important. The act of fasting is said to redirect the heart away from worldly activities, its purpose being to cleanse the inner soul and free it from harm. It also teaches Muslims to practice self-discipline, self-control, sacrifice, and empathy for those who are less fortunate; thus encouraging actions of generosity and charity (Zakat).
It becomes compulsory for Muslims to start fasting when they reach puberty, so long as they are healthy, sane and have no disabilities or illnesses. The elderly, the chronically ill, and the mentally ill are exempt from fasting, although the first two groups must endeavor to feed the poor in place of their missed fasting. Also exempt are pregnant women if they believe it would be harmful to them or the unborn baby, women during the period of their menstruation, and women nursing their newborns. A difference of opinion exists among Islamic scholars as to whether this last group must make up the days they miss at a later date, or feed poor people as a recompense for days missed. While fasting is not considered compulsory in childhood, many children endeavour to complete as many fasts as possible as practice for later life. Lastly, those traveling (musaafir) are exempt, but must make up the days they miss. More specifically, Twelver Shī‘ah define those who travel more than 14 mi (23 km) in a day as exempt.
In addition to fasting, Muslims are encouraged to read the entire Qur'an. Some Muslims perform the recitation of the entire Qur'an by means of special prayers, called Tarawih, which are held in the mosques every night of the month, during which a whole section of the Qur'an (Juz', which is 1/30 of the Qur'an) is recited. Therefore the entire Qur'an would be completed at the end of the month.
Ramadan is also a time when Muslims are to slow down from worldly affairs and focus on self-reformation, spiritual cleansing and enlightenment; this is to establish a link between themselves and God through prayer, supplication, charity, good deeds, kindness and helping others. Since it is a festival of giving and sharing, Muslims prepare special foods and buy gifts for their family and friends and for giving to the poor and needy who cannot afford it; this can involve buying new clothes, shoes and other items of need. There is also a social aspect involving the preparation of special foods and inviting people for Iftar.
Muslims all around the world will abstain from food and drink, through fasting, from dawn to sunset. At sunset, the family will gather the fast-breaking meal known as Iftar. The meal starts with the eating of a date — just as Prophet Muhammad used to do. Then it's time for the Maghrib prayer, which is the fourth of the five daily prayers, after which the main meal is served. 
Over time, Iftar has grown into banquet festivals. This is a time of fellowship with families, friends and surrounding communities, but may also occupy larger spaces at mosques or banquet halls, where a hundred or more may gather at a time.
Most markets close down during evening prayers and the Iftar meal, but then re-open and stay open for a good part of the night. Muslims can be seen shopping, eating, spending time with their friends and family during the evening hours. In many Muslim countries, this can last late into the evening, to early morning. However, if they try to attend to business as usual, it can become a time of personal trials, fasting without coffee or water.
Charity is very important in Islam, and even more so during Ramadan. According to tradition, Ramadan is a particularly blessed time to give in charity, as the reward is 70 times greater than any other time of the year. For that reason, Muslims will spend more in charity (sadaqa), and many will pay their zakat during Ramadan, to receive the blessings (reward). In many Muslim countries, it is not uncommon to see people giving food to the poor and the homeless, and to even see large public areas for the poor to come and break their fast. It is said that if a person helps a fasting person to break their fast, then they receive a reward for that fast, without diminishing the reward that the fasting person got for their fast.
Sometimes referred to as "the night of decree or measures", Laylat al-Qadr is considered the most holy night of the year. Muslims believe that Laylat al-Qadr is the night in which the Qur'an was first revealed to the Prophet Muhammad. Also, it is believed to have occurred on an odd-numbered night during the last 10 days of Ramadan, either the night of the 21st, 23rd, 25th, 27th or 29th. Shiites also commemorate the attack on Imam `Ali ibn Abi Talib and his subsequent martyrdom every year on the 19th and 21st of Ramadan.
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