For the Sunni this is a voluntary fast day only. For Shi'ites however, the day is of very great importance. In many places processions will move through the streets carrying 'coffins' as the murder and funeral of Hussein is recalled. Men will often follow in the procession's wake beating themselves to draw blood so as to express their empathy with Hussein's suffering. Women often break their glass bangles - something they only otherwise do at the death of their husband.
In many places 'passion-plays' (Ta'ziya) are enacted depicting the events of Hussein's life. These can become very emotional affairs with a lot of audience involvement.
