For millions of Muslims around the world, the holy month of Ramadan is a time for reflection and abstinence. It is a time when those who follow Islam are supposed to clear their minds of distractions and dedicate more of their attention to their faith.
It is probably more noticeable for those who are not from traditionally Muslim countries, because Ramadan is adhered to more strictly by so many on such a large scale. But Islam is not the only religion that fasts - indeed many faiths at some point in the calendar require their followers to offer some level of abstinence.
Fasting tends to be from food, drink, smoking, and acts that give pleasure such as sexual intercourse and listening to music - and while the reasons might appear to vary between religions, it is largely to focus the minds of those observing their fasts on their faith.
Here we look at religions that fast and what is involved:
Muslims: The Muslim fasting month of Ramadan lasts a month and the fasting aspect is acknowledged during daylight hours.
Unlike many other religions, fasting during Ramadan is a requirement of all Muslims who have reached puberty and those whose health permits them to fast – it is one of the five pillars of Islam and therefore compulsory.
During the holy month, Muslims believe that they are cleansing their bodies to get closer to God. It is believed in Islam that food, drink and other desires stand in the way of connecting with their faith – in short, they believe these work as a distraction.
Ramadan is also a philosophical time of the year during which many believe they learn to be more patient and increase their self-control - feeling less inclined to take part in gossip and other negative thought processes - which they believe make them better people.
Some Muslims also choose to fast voluntarily on special Islamic days throughout the year, such as the Day of Arafat, the day before the major Islamic holiday of Eid al-Adha.
Christians: For 40 days (excluding Sundays) from Ash Wednesday to Holy Saturday, Christians observe Lent. Like Ramadan this is a time of repentance, but it also serves as a preparation for Easter.
The belief is that the 40 days fasting reflects the time Jesus spent fasting in the desert.
But unlike Ramadan, does not involve a complete abstinence from food for any particular time. Instead, those of various denominations of Christianity, including Catholicism, might eat more sparingly – but it is more common for an individual to give up a particular food or habit.
For many, it is a time for self-discipline with some quitting smoking, or avoiding the television or eating sweets. Some might say they have given up gossip or lying. But unlike Ramadan, there is not the same obligation to observe this event.
Theoretically, Lent is meant to be a time to be humble and of self-constraint. It is not uncommon for people to discuss what they plan to give up for Lent in the form of a personal challenge, which they might share with others.
Judaism: Jews fast for six days in the year – although only two of these days are deemed to be so important that all must observe, except for those whose health would be negatively impaired.
The most important day of the year in the Jewish calendar is Yom Kippur and fasting is expected of every Jewish man and woman above the age of puberty (bar mitzvah and bat mitzvah). So important is the fast on this day that those who need to eat are encouraged to consume as little as possible – without endangering their health.
The second most important day of fasting is called Tisha B’Av, which marks a number of anniversaries in the Jewish faith and traditionally ends a three week mourning period, during which Jews reflect on the various tragedies that their people have suffered, including the Holocaust.
There are four other days of fasting through the year, although these are not deemed to be as important and are not compulsory.
Hinduism: Fasting is a more personal decision for Hindus – depending on their own individual beliefs and customs. But it remains an important part of Hinduism.
The days that people fast vary a great deal, but they tend to involve certain religious days of the month and week. For instance, in southern and northwestern India it is common to fast on a Tuesday - which is dedicated to their goddess Mariamman. This particular fast last between sunrise and sunset, but followers may drink liquids during this time.
Likewise Thursdays are a common day for fasting among Hindus living in northern India. The fast started with a story. People will traditionally wear yellow clothes, and eat meals that are yellow.
As with the days, the methods of fasting also vary depending on the culture and personal beliefs. That said, strict fasting, will mean the individual does not consume any food or drink during the fasting time.
It can also mean people limiting themselves to one meal during the day, or restricting themselves to a certain food, or alternatively abstaining.
Buddhism: Strictly speaking, Buddhist monks and nuns don’t fast, but they do abstain from food after the midday meal which is aimed at aiding meditation and good health.
Indeed many health professionals do suggest that eating in the morning is healthier than the more common approach of having the main meal of the day in the evening.
Buddhists will fast during times of intense meditation and abstain from over indulgence.