There exists several ways to move from one point to another, each with different kinds of advantages and disadvantages. For example, you might have cheap train tickets for use but not have the time to spend on the long train journeys. Let us compare a few of them against varying parameters.
On short trips, flying would not save you any time as you spend a lot of time at the airport waiting for your plane to depart not to mention the amount of time you spend driving there. Time spent driving on any trip especially considerably longer ones, is time wasted as you cannot do much while driving.
If you, however, take the train or bus, you can sleep, read, or work before you get to your destination. Overnight trains might be slower than a plane but if you spend part of that time sleeping on a comfortable bed in the train, you might save on time and even cash that you would have spent to get a hotel room.
Air transport might be cheap at times but you have to buy the tickets way ahead of your trip to get the best rates and if you happen to make a last minute purchase, the penalties are almost punitive. Trains and buses however are a bit flexible in this regard and their penalties for late purchase are bearable compared to those of air travel.
You might also be able to get cheap train tickets that might lower your travelling costs. In addition, in case you are travelling as a group, it becomes cheaper if you drive, as you can car pool and share the costs. This is, however, not possible on trains, planes or buses.
When it comes to comfort, trains take the lead. They offer more leg room and you get to bring larger baggage and use your electronics freely. You can even get a bed to sleep on at a little extra cost. Cars follow in second, as you can stop and rest whenever you want then planes are at the tail end.
Measured in fatalities per mile, cars probably are the least safe. Here is the math: if say, 70 people need to take a 5000-mile trip, they would only need one plane. However, if they used cars and assuming there are two people per car, they would need 35 cars.
Thus the trip would only be 5000 plane miles but it would be 175,000 car miles given there are 35 cars on the same trip thus the risk of exposure is 35 times higher per individual.