Hi-pass means the frequencies ABOVE your setpoint will be audible. Low-pass works the opposite; all frequencies below the setpoint will be your audible frequency band. A bandpass setting includes both a high and low crossover, effective creating a pass band within the setpoints: for instance the lowpass will be set at 1KHz, so everything below that will be audible up until you reach your highpass setpoint, such at, let's say 50Hz. So your effective passband or frequency range of said output would be 50Hz-1KHz.
Examples:
Lowpass set at 80 will filter frequencies above 80Hz while passing those below.
Highpass set at 80 will filter frequencies below 80Hz while passing those above.
This is a very generic answer and does not take slope or filter type into effect. You could easily get lost there with effective power filtering, which is basically what the crossover is doing, and also phase shift. We wont begin to get into that and you really need not worry about it unless you are competing.