Professions, occupations and hobbies... Elite is loaded with opportunities for all of these.
Primary Professions:
Trader - Freighter captains, hauling goods from Point A to Point B and Beyond
Pirates - Prey on Traders, Smugglers and Miners, stealing those goods to sell at Point C instead.
Miners - Like Traders, depend on selling their goods somewhere else. They just happen to work to get them, rather than purchasing them.
Explorers - They want to know what's out there.
Bounty Hunters - Prey on pirates, and deliver them the only justice Elite knows: death.
Mercenaries - Got a War? Got Credits? Mercenaries will flesh out your navies, in exchange for compensation.
Smugglers - When Point B needs what Point A has to offer, but aren't allowed to sell in the open market, Smugglers will be there to provide those goods not otherwise obtainable.
Transport Pilots - When You've Had Enough of Point A and want to know if the grass really is greener at Point B, or you're simply long overdue for a vacation, the Transport Pilot is the person to see.
Occupations:
Not quite the same as Professions, the Occupations are sub-sets of professions.
Researcher - an Exploration sub-set. The Explorer may find the planet that is home to ancient ruins, but it is the researcher who plants themselves there, vowing to unlock all the lost secrets to be found. Many researchers are also explorers out of necessity.
Special Operative - A mercenary sub-set, these folks will do the dirtiest work that needs done. Need data stolen? Need an enemy general marginalized? Need to demoralize an enemy by taking out the transport full of their relatives? Find yourself a Special Operative, and consider it handled.
Thugs/Enforcers/Psychopaths - Largely BGS related, these are the folks who are willing and able to destabilize entire star systems making them ripe for conquest, or make a place too unpleasant for others to try to take over. Many PVP players fall into this occupation, either by choice or by deed. Some are Power Players, others just playing with the own power.
9 to 5'er - Mission runners, working for one or more factions. They're the backbone of galactic civilization, and may be involved in one or all of the Professions.
Scavenger - Part explorer, part trader, the Scavenger scours the galaxy for lost cargo to make enough credits to rub together. A good scavenger can make every bit as much as miner or trader, sometimes more, as their operating costs are considerably lower, and they generally don't draw as much interest from Pirates.
Hobbies:
These generally don't earn anyone a living, rather they tend to cost credits instead.
Racer - Planetary or Transgalactic, these folks just want to get there first - where ever first may be. Often unarmed, the racer's ship is little more than something to hold them to an engine.
Mentor/Monkey Trainer - Some people are natural pilots, others need help finding the mailslot. This is where mentors come in to play. Getting a new commander started on a path and watching them succeed is its own reward.
Fuel Rats/Repair Rangers - The galaxy would not be the same without Fuel Rats, and with the advent of the Repair Limpet, the opportunity for player-to-player services has expanded. These steadfast folk brave the deep (and not so deep) reaches to save those hapless souls that find themselves stranded in the black. Likewise, Repair Rangers bring Repair Limpets to fix battered hulls of those unfortunate souls who've managed to abuse their ships far from home.
There are plenty of other Professions, Occupations and Hobbies I haven't listed, but these are all the ones that come to mind.
