Fasting in Islam is to refrain from eating, drinking,to obey the Allah's order.
Fasting ,is one of the most important rituals in Islam. Muslims must abstain from a number of activities including eating and drinking from dawn (fajr) to maghrib adhan to obey God's command. Fasting is one of the ten Ancillaries of the Faith (Furu' al-Din), and it has been obligatory in other religions in different fashion.

Fasting is a mean to seek proximity to God, and it increases one's piety. It purifies the soul and the body, atones for some sins, and also strengthens self-control and sympathy [towards the poor]. In addition, it inculcates a sense of fraternity with the needy and hungry. According to fiqh fasting is categorized into four types: wajib (obligatory), mustahab (recommended), makruh (disliked) and haram (forbidden). Moreover, according to some hadiths, fasting is categorized into three levels in 'irfan: common fasting, special (khas) fasting and the most especial fasting (khas al-khas).

Fasting has been considered as one of the pillars of Islam. It is obligatory for every mature, rational and healthy Muslim. The verse on fasting was revealed in Sha'ban 28, 2/624: "O you who believe! fasting is prescribed for you, as it was prescribed for those before you, so that you may guard (against evil)."(Q 2:183). However some of its details on the conditions of fasting were changed and some were abrogated.

The ritual of fasting is an act of worshiping God. However except obligatory fasting days in the month of Ramadan, there are numerous recommended fasting days.