While "Starfleet Command" refers to the operating authority of Starfleet, "Command" is also a division within the fleet. They specialise utilising the concept of "C3," command, control, and communication. They are trained to supervise and direct others. Members of the Command division - even those who are not senior officers - are trained in leadership and tactics, giving them the ability to organise and mobilise Starfleet crews and assets to perform various types of missions.
In some cases, Command officers aren't even supervising or controlling people: in the case of helmsmen, they're controlling an entire ship. The division also comprises officers associated with the Diplomatic Corps and the Judge Advocate General (JAG) Corps. Some officers have been in Command since they graduated, but others have made the change over the course of their careers, going through the Command Training Programme to change division.
Away Team Coordinators are critical in arranging missions off the ship or starbase. When an away mission is first proposed, they work with senior staff to analyse the goals of said mission and how to accomplish those safely. They advise on terrain and movements, equipment required, and which officers would be best suited to the task. They may join the away team themselves or help to provide advice remotely from the command deck or bridge.
Crew Resources is the modern equivalent of HR. They handle the onboarding of people newly transferred aboard, performance management, aiding in career progression, enforcing health and safety regulations, managing absences, and helping leavers (be that people being posted elsewhere or those retiring from the fleet.) If issues ever arise between crewmembers, they can act as intermediaries and work to resolve the problem.
Officers from the Diplomatic Corps that are sent on regular postings are known as Attachés. They represent Federation interests, handle foreign relations, negotiate, and can act as envoys. All are highly trained in understanding the customs and culture of other powers, be that close allies in the Khitomer Alliance, or species and factions that the Federation have poor relations with. In first and second contact scenarios, these officers take point.
While Diplomatic Corps officers handle representing the Federation in diplomatic cases, Fleet Liaison Officers are spokespeople who represent the interests of their home government's fleet. They act as a means of communication between other forces, agencies, or civilian entities to coordinate, resolve issues, and ensure smooth operations. In times of large-scale fleet engagements they can also act as a bridge between their current posting, such as 777, and other Starfleet crafts in the area, ensuring smooth communication.
These are the crew who fly the ship, often also known as helmsmen, conn officers, helm officers, or navigators. They are trained to control speed (from impulse to warp and utilising transwarp gates,) attitude, and also to utilise various forms of navigation. All have multitudes of attack patterns and evasive manoeuvre sequences memorised. Given that 777 is a starbase and that the Eventide is only deployed when necessary, most flight control officers also double as shuttlecraft pilots and do this in the meantime.
The Judge Advocate General's Corps administer legal affairs. These officers comprise judge advocates, lawyers, clerks, and more. They can offer legal assistance to crew members, handle claims and environmental law (e.g. if assets or land was damaged by Starfleet), advise commanding officers of their own and international laws, and persecute or defend officers in legal cases (such as court martials) when required.
Media Relations Officers are the main point of contact for any media/press enquiries regarding Starbase 77, Starfleet activities nearby, activities between the Khitomer Alliance, or even cases involving civilians if required. Their role involves handling enquiries from external and internal sources, handling sensitive or confidential information to deal with requests for information, and writing and proofreading press releases for external distribution.
Morale Officers work to keep up the mood throughout Starfleet crew members. This can be during normal business as usual or on away missions if they attend. They focus on the well-being and satisfaction of the crew, which in turn leads to better performance. This can revolve arund things like ensuring a good work-life balance, creating engaging activities for people to attend, resolving issues, and working to increase team spirit.