It's the far future and mankind has spread out widely from Earth, thanks to the discovery of a method of faster-than-light travel over a thousand years ago. So far no one has met any living representatives of other intelligent species, although explorers have discovered the ruins of alien civilisations.
Politically the galaxy is extremely fragmented. It is not uncommon for a populated planet to contain several competing nation states, and even the biggest empires are contained within single star systems. Communications between systems take place at the speed of spaceship travel. There is no galactic equivalent of the UN. Trading between star systems is controlled by various galactic banking organisations, which are generally run from off-planet. The banks also act as a kind of galactic passport control. If you want to take a spaceship to a civilised system and be allowed onto the surface when you get there, then the ship pretty much has to be sponsored by a bank that has dealings with the local power. There are of course plenty of uncivilised systems to which you can travel. Getting to work for a bank is the best way to get to travel the galaxy and is also supposed to be very lucrative. Banks are not short of applicants for jobs. Space travel is made economically possible by two technologies: the hyperspace drive and the teleport. Teleport is used to get things from ship to surface and vice versa, and also for high speed surface travel on some planets. Most don't allow it to be used close enough to centres of population to be practical, as the technology is somewhat unstable. It does not work over long enough ranges to be used between planets. Teleport requires large amounts of infrastructure at both ends. Practically all spaceships have a teleport station on board. Civilised planets tend to have a few large teleport complexes, situated a safe distance away from any cities, through which everything going to or from a spaceship has to pass. Once you're in orbit you get between systems by using hyperdrive engines. The physics behind these is understood by relatively few people. You can plot a hyperspace course to your destination based on the known characteristics of your particular hyperdrive, but you can never be sure exactly where you'll come out. Most pilots rely on well known, preprogrammed courses. New, efficient courses are very hard to work out (and vary for each type of hyperdrive). Get a new course wrong, or even be slightly unlucky, and you'll never be seen again. New, efficient, or otherwise special routes are therefore valuable secrets to have. Some hyperdrive designs are more accurate and therefore easier to navigate with (or at least there's more data available on their idiosyncrasies) than others. Also some hyperspace physicists have the skill to plot faster courses than others. One good thing about hyperspace travel is that you don't experience time spent in hyperspace, so travel seems instantaneous even though it's not. The exact time taken can't be predicted in advance for a new route. Hyperspace navigation is an art even with a well-understood hyperdrive. All other things being equal, the longer you're prepared to allow the journey to take, the more accurate the end position will be and vice versa. The presence of strong gravitational fields in the places you enter and exit hyperspace also affects accuracy, so sensible people try to do this well away from planets. This has the effect that all inter-system journeys appear to the travellers to take about the same amount of time from end to end: a couple of days. Several organisations have active research programmes into hyperspace travel with endpoints on planetary surfaces. So far none of the volunteers who tested these drives has ever been seen again. Spaceships tend to be physically large as they have to contain all of the technology for hyperdrives and teleports. They obviously have to be constructed in orbit and this requires complicated facilities, so most systems don't have a local shipbuilder. This makes them extremely expensive commodities. However, ships last for a very long time if carefully looked after. The PCs want to get off planet for some reason: to see the Universe, to avoid debt collectors, to get over a tragic love affair...the usual sort of stuff. They have filled in the application form for the Vega Trading Company's annual recruitment exercise, and after a long and competitive selection procedure have been accepted. The PCs clearly all have something the VTC's HR department wanted; whether it was useful skills, valuable assets, or simply the return of certain photographic negatives is up to the individual player. Now they are about to get their first assignment and go outside their home system for the very first time.