Muharram is not a particular day, but the name of a month that marks the beginning of the year according to the Islamic calendar.
Muharram commemorates the suffering and martyrdom of Iman Husayn bin Ali, , grandson of Prophet Muhammad and the entire family of the Prophet at the hands of the Abbasid ruler Yazid at Karbala in Iraq in 61st year after Hijra.
The Shi'a branch of Islam is the main sect that commemorates the martyrdom of Husayn ibn Ali by arranging 'majalis' (gatherings) to review Islamic teachings and to commemorate Husayn's sacrifice. The mourning reaches its climax on the tenth day of Muharram, known as Ashura.
On the 10th day of Muharram, large processions are formed and the devoted followers parade the streets holding banners and carrying models of the mausoleum of Husayn ibn Aliand his people, who fell at Karbala.They show their grief and sorrow by inflicting wounds on their own bodies with sharp metal tied to chain with which they scourge themselves.
For the duration of the remembrance, it is customary for mosques to provide free meals (nazar) on certain nights of the month to all people. These meals are viewed as being special and holy, as they have been consecrated in the name of Husayn, and thus partaking of them is considered an act of communion with God, Husayn, and humanity.