What does RDM's job abbreviation mean in hotels?

The room service manager smiled when he saw me go upstairs. Room service manager? I never entered the hotel at first sight. Do you know what room service means? In the hotel, this is room service, which is managed by western food. Although there are also room attendants knocking at the door to report room service, they are all accurately reported to the housekeeping department, that is, the catering and room service departments are collectively referred to as the front office department and the housekeeping department. You merged two completely different departments into one. By the way, the title of the real housekeeping department is director, not manager.