Someday hopefully a lot of people will be working and living throughout the solar system. When that day comes there will be companies providing passenger service from orbit to orbit for a ticket price that makes it profitable for them to operate. There will probably be many different engines types in use (chemical, nuclear, solar sails, etc) with varying levels of service and accommodations.
Landers will probably be unique for each destination and run by different companies. They will also sell tickets to ride for a profit. Makes one wonder if Tom Hanks will someday make a movie about being stuck in orbit without the price of a ticket?
What about the passengers? What will there motivations be? In the near future, they probably won't be the actual purchaser of tickets. They will mostly have sponsors that want them someplace other than where they are for their own reasons. One being that they will need people with certain skills for work in certain locations.
We can define space faring as a time when people do buy their own tickets to ride.