Even though Good Friday is the most solemn day in the Holy Calendar, it is not a holy day of obligation. In fact, it is the only day that mass is not celebrated world wide in the Catholic Church. Instead, the service is a very somber one where everything is stripped down to a minimalist state. Lights are dimmed. Church decorations are not present. Music and bells ringing are eliminated. The clergy enters the church in silence. All of this gives way to allowing the cross to be the central object of contemplation. There is literally, nothing left to distract one, save the inner mind.
Good Friday is a day of fasting-if possible, total abstinence from food until afternoon. Greek Christians will eat lettuce dipped in vinegar-recollecting the sustenance offered to Christ when he was crucified.
There are many ways around the world that Good Friday is celebrated and observed. The underlying theme, however, is one of sacrifice for us all-be it represented by way of a solemn service, parades with a crucifix or a Passion Play. The commonality that is shared by Christians throughout the world is the recognition of sacrifice which in turn, leads to the triumph that the celebration of Easter brings.