The power levels you can get from a programmer depends on the model of your vehicle and the tuner itself. However, there are some basic levels of power that you can get from most programmers.
The stock setting is not a power level per se but if you select it, the factory settings of your vehicle will be restored. Getting the factory setting back is essential before you take the vehicle for an emissions test or maintenance.
Mileage or economy setting may not always be overtly offered as a power level. However, you’ll find out that most tuners do offer ways to improve fuel consumption.
The towing power level is to help you run your vehicle on a higher gear by increasing the horsepower. You might need this power level when you’re towing heavy loads.
Off-roading power levels and race levels are offered by some tuners. The former is meant for gas-driven off-road vehicles on uneven terrain. The latter is meant for racing or fun driving by increasing the horsepower.