This video illustrates tapping more than once during the beat. Possible combination are tapping on '2' + '3', on '3' + '4' or '2' + '4' with the step coming on the '1' always - the downbeat. (Using the system of count '1-2-3-4' for each beat, '1' being the downbeat, '3' being the upbeat or exact middle, and '2' and '4' being the places inbetween or the quarter beats).
Early tango was known as tango criollo, or simply tango. Today, there are many tango dance styles, including Argentine Tango, Uruguayan Tango, Ballroom tango (American and International styles), Finnish tango and vintage tangos. What many consider to be the authentic tango is that closest to that originally danced in Argentina and Uruguay, though other types of tango have developed into mature dances in their own right.