A memorial service is a service without the body present and can vary in ceremony and procedures according to the community and religious affiliations. Some families prefer public visitations followed by a private or graveside service with a memorial service later at the church or funeral home.
Because the body is not present at the memorial, disposition may take place either before or after the service. You can hold a memorial service instead of a funeral, or in addition to it. For instance, you might have a funeral in the town where the person lived and died, and a memorial service later in the town where he/she grew up.
It is common to have a memorial service following a cremation. When you choose a cremation its important to have a memorial service to have the closure needed in the grieving process.