It is a common mistake to say that tango is the music of Argentina. Tango is the cultural expression of the Rio de la Plata, which includes Buenos Aires, Rosario and Montevideo. 

Unlike most other dance styles, Tango has no fixed rules for tempo or steps. At every beat of the music, the leader has the option to lead the follower to step in any one of several directions or even to Not step, i.e. to pause. The ability - if not the expectation - to add pauses and tempo changes to accompany the music is a key element making Tango what it is - a dance of infinite variety: no two dances are ever the same. Just as every partner, every song, every night, is different, the dance that results when these unique elements are brought together for this one moment in eternity is itself unique and can never be repeated. 

Another characteristic of the music is that its tempo is not always regular. Tempo changes are common, and sometimes there are passages where the "beat" is suspended or imperceptible. While this can make some music challenging to dance to, it also gives the dancers wide latitude in using pauses and rhythm changes to interpret the emotional content that they feel from the music and from their personal moment of reality with this partner, on this dance floor, in this embrace. 

Social Tango is not choreographed. Every component of every step - timing, speed, and direction - is led. This requires the follower to be paying full attention every moment to the various, sometimes very subtle, body movements that constitute the leader's signals to her. She must suspend all anticipation, expectation, and analysis. She must be balanced and poised, waiting, waiting, waiting to respond to his lead.  

But the lead-follow dynamic is not one-directional. The leader too must listen and wait for his follower to respond. The leader does not step until the follower has begun to step, until she has committed her momentum. She may not take her step exactly as he had intended. So he must accommodate her, adjusting his step to be in synch with her, so that when the two of them land their steps, they are precisely together. The flow of the dance is dictated by the bodily communication between them. It is inherently intimate, on a deep level, and transcends thought and reasoning. 

I once talked to a young woman who was new to Tango. She said she was adventuring into this unknown territory because of the impact of her first experience seeing tango. It was at a New Year's Eve celebration, and she had been surprised and confused by what she saw. The dancers were dancing as midnight approached, and though there was some announcement of the impending zero hour, the dancers just continued dancing. When midnight arrived, the music was stopped for a few seconds of token revelry, but then, almost immediately, everyone went back to dancing. She could not understand how a dance could be so enticing as to supersede the traditional, centuries-old celebration of the New Year. But, like anyone who has danced Tango for any length of time, I just smiled and nodded with understanding, shrugging at my inablility to adequately explain. I told her she would just have to try it for herself.