Android supports 4 dialog boxes:

AlertDialog:

An alert dialog box supports 0 to 3 buttons and a list of select-able elements, including check boxes and radio buttons. Among the other dialog boxes, the most suggested dialog box is the alert dialog box.

ProgressDialog:

This dialog box displays a progress wheel or a progress bar. It is an extension of AlertDialog and supports adding buttons.

DatePickerDialog:

This dialog box is used for selecting a date by the user.

TimePickerDialog:

This dialog box is used for selecting time by the user.