Star Travel
RogerBW
The basic idea is jump points. You go to a jump point (which are not easy to find, but in civilised systems they are surveyed and marked), turn on the stardrive, and find yourself on the other side. Any given jump point leads to exactly one other jump point; if you want to go somewhere else, you fly across the destination system to another point and use that.
Jump points are 5-40 au out from the star, in the direction of the destination star (roughly one AU per lightyear); if you think there might be a jump link from star A to star B, you have a fairly good idea of where to look for it. A surveying ship can detect a point that it’s inside without going through. Points can’t generally be detected at a distance; they don’t interact with real space.
A ship doesn’t need a distinct stardrive system: committing to a jump is a matter of setting up the right pattern of electrical charges across the hull at the right time and place.
A “point” is a non-trivial three-dimensional volume (tens of miles across), and it can of course be mined, though this is expensive. It’s disorientating, to humans and to computers, to pass through hyperspace; the cautious peacetime skipper will make transit slowly.
The closer you are to the middle of the point, the less stress on the ship, but the more predictable your exit position.
If you would interpenetrate a significantly solid object on the far side, nothing happens when you turn on the drive. But a warship skipper can always try going through off-centre; filling a multi-thousand-cubic-mile sphere is impractical.
Stars link to other stars which are “close” in a five-dimensional coordinate system: XYZ, a value based on spectral type, and absolute luminosity. The trick is therefore that a pair of similar stars will create a link over a longer distance than a pair of dissimilar stars, so you might go down a long sequence of M-type dwarves to get from one habitable system to another.