All Adult Citizens are members of a service group which provides useful services to the Bubblegum Complex community. Most sectors contain an even mix of service groups, although some specialty sectors do exist (NRA is all Armed Forces, HWD sector is mainly HPD&MC, POW sector is Power Services, etc.)
Armed Forces is the combined Army, Navy, and Air Force of Bubblegum Complex. They defend Bubblegum Complex against Communist assault in theory. In practice, they cause massive destruction and expend huge amounts of ammunition because they are a bunch of trigger-happy nutcases with nothing to take out their aggression on.
CPU--Central Processing Unit
In theory, this service group coordinates all of the other service groups and provides information and programming services as needed. In practice, they make up huge numbers of useless forms and stack them to use as kindling during cold spells.
HPD&MC--Housing Production and Development and
HPD&MC does several things. They build and maintain all housing facilities, they grow food and run the cafeterias, and they provide Alpha Complex entertainment. In practice, the housing collapses, the food often kills, and the entertainment numbs the mind. But if you're high clearance, you get the best food, housing, and entertainment. They also effectively maintain harems for high programmers.
Internal Security is in charge of rooting out crime, corruption, and communism, finding those who are a danger to Alpha Complex and removing them before they can infect others. In practice, they are a political police force, spying on everyone and killing anyone who looks at them funny for treason. Many of them abuse their position to blackmail anything that moves.
They maintain the nuclear reactors, solar cells, giant mutant hamsters in hamster wheels, and other sources of power, as well as the wiring systems which transmit the power and the batteries which store it. In practice, they really do all of those things. Badly. Most of them aren't cleared to know anything about the nuclear reactors they maintain, and much other crucial info is too high clearance for most power services personel. As a result, over half die in the first year. On the other hand, this is one of the rare places in the Complex where competence really does pay. If you don't die in nuclear fire.
PLC--Production, Logistics, and Commissary
PLC makes and distributes all the goods needed by the citizens of Bubblegum Complex. In practice, they never produce enough of the needed goods and overproduce luxury trash for the High Programmers. You have to bribe clerks to get needed goods, or shoot them. And sometimes they decide to charge you for things you never ordered, because the goods are missing and SOMEONE has to take responsibility. It might as well be you.
R&D--Research and Development
Research and Development is the cutting edge of Bubblegum Complex technology research, creating new devices to improve the life of citizens. In practice, it's a nuthouse of mad scientists with no idea what they're doing. They create insane devices and force people to test them, usually resulting in mass casualties. Still, they do have a handful of successes like Bouncy Bubble Beverage to their name. (Sure, it was INTENDED to be a quick drying glue...)
They fix anything that breaks, from bots to autocars to lightbulbs to damaged weapons. In practice, just like Power Services, they often have no idea what they're doing because the manuals are too high in clearance for them to look at. And the competent ones demand bribes.
The Troubleshooters are a multi-service group task force which deals with problems that don't fall in the responsibilities of the service groups or which can't be trusted to them. The ADPolice of MTA sector are a local Troubleshooter task force dedicated to dealing with renegade bots. The ADPolice usually calls upon IntSec and Tech Services for most of its agents.