The Lunatics Team breaks down the various departments to just three divisions. This may not be all that star trek has to offer, but it will be most of it. Each of the three divisions will have there own color to set them apart, for the purposes of this RPG, we will be using the 2370 choices of Red, Yellow, and Blue.
Command
The first division will be Command, however, starting a s recruit you will only have the helmsman to choose because it is reserved for the leadership roles on a star ship. This will include the Flight Controller, also known as the helmsman.
Operations
Next up is the Operations division, personnel will be wearing Yellow to set them apart, however they do have multiple departments within this division. The first being Engineering, handling all the maintenance matters as well has keeping all the primary systems available. The second being Security, which as you might guess would handle the tactical station, and security of the ship and crew.
Science
Finally we have, what I would call the biggest division, Science. Although there are many departments within this division, you will find them all wearing the 2370 blue. We are curious beings and need to need people to monitor the sensors, research the unknown, even theorize or handle experiments. Sadly, the other half would require a bit more training, and that is the medical staff, Doctors, Surgeons, Medics, and even biologists may need a bit of medical training to understand biological lifeforms, viruses, and bacteria.