To 3D print a model file, it must first be sliced. This process is where a model will get all of it's settings.
3D printing a 3D model isn't as easy as drag-and-drop. First of all, a 3D model file usually only contains mesh data (and sometimes textures). Where would you change the speed, quality, size, etc? For a 3D printer to print a model, the model must be converted into a different file that is a list of commands telling where the printer should go, at what speed, etc. The kind of programming that a printer understands is called gCode.
When I slice a file, I use a program called Cura. You can most 3D model file types (like obj and stl), and then export to a gCode file. Of course, you should not consider the gCode file as a 3D model, or Cura as a model converter. When you import a model, you can choose many different settings. Some of them have to be specific to the filament or printer you are using, like the diameter of the plastic and the flow of how fast it goes into the extruder. Others, however, can be decided upon depending on the print itself (things like quality or whether or not to add supports). This allows you to get the right ratio of speed to quality, and sometimes you can print a high quality print in a short amount of times by choosing the right settings.
The first setting in the list is the layer height. During the printing process, models are printed by laying one layer on top of another. The layer height decides how many layers to fit into a space. The more layers, the higher quality, since the lines that you usually see on prints wouldn't be there. However, it takes longer since there are more layers to print. If you do less, then there would be visible lines on the print, though it does go faster since there are less layers to print. To little layers, however, and it won't bond with the layer underneath it.
The next setting is shell thickness. This is how thick (or strong) the layer on the outside will be. The reason this is a setting is because sometimes you would want to print hollow models but don't want a weak shell, or even semi-hollow models. Usually, though, you wouldn't change this. Another setting is the bottom and top thickness. When printing with 50% infill, it creates a grid pattern on the inside without fully filling inside. The bottom and top thickness is how many layers to print before it starts the grid pattern and how many before the surface of the print is done. The fill density settings is next. The less you fill it, the more hollow it will be. When it becomes hollow, it creates a sort of honeycomb grid pattern inside. Less infill will drastically speed up the print, but make it feel cheaper due to light weight. The more infill, the longer the print will take. However, it is worth it for that strong plastic feel. This is where you could change the speed to a high amount, and fill the inside completely.
The next setting is speed. This setting will change the time it takes to print the most. The value of this setting will most likely be specific to the piece you are doing. The higher speed, the lower quality, and it may be that the print could fail if this setting is too high. A lower speed helps the print hold together, and make it much stronger during and after printing. Sometimes, for large prints without delicate parts, I will make the speed very high. Usually, however, (especially for overnight prints), I will make the speed lower. Usually when quality matters or time doesn't. The next two settings are the nozzle and bed temperature. These are specific to the plastic you are using, and once you can find a nice temperature (or use the default) you usually wouldn't change it again.
A really nice option is an option to add supports. Due to the way printer do their printing (layer on top of layer), overhangs do not print well (if at all. Floating pieces don't print). However, when you add the supports option, it adds a weak and easy to remove support underneath overhangs and floating pieces. This wastes a tiny (very tiny) bit of plastic, though the main problem is that it takes longer to print. However, for overhangs, it is necessary. Probably one of the big satisfying things of life is digging into a print with pliers and removing the supports. The collapse when pressed, making them come off in chunks. Normally, though, you wouldn't use supports.
Another option is the platform adhesion option. You would use this when dealing with warping and/or prints not sticking to the bed. The raft adhesion option prints a raft (hence the name) underneath the model, meaning that it warps instead of the print. It also means more of the print is touching the bed. Like the supports, it comes off of the print fairly easily. The next option is the brim option. It is similar to the raft, except instead of adding itself under the model it wraps around the model, sort of like a skirt. It prevents warping better, but not so much with adhesion problems. Both options take a lot longer to print, so it is better to get a heated bed or use a better adhesion solution (like ABS slurry).
There are some other more specific options, like the speed at which parts of the model print at, but almost all of the others have values specific to the printer.