REDCAP is an acronym for 'Regimental Enlisted Detailed Clerk and Assistant Provost'. It is a job title in the United States Army that was created in the late 19th century. The role of a REDCAP is to provide administrative support to the regimental staff, such as maintaining records, preparing reports, and handling correspondence. The PORTER is a subordinate of the REDCAP and is responsible for carrying out various duties, such as delivering messages, transporting supplies, and assisting with the maintenance of the regimental headquarters.