Here is some general information about tango, from WkiPedia
"Argentine Tango consists of a variety of styles that developed in different regions and eras, and in response to the crowding of the venue and even the fashions in clothing. Even though they all developed in Argentina and Uruguay, they were also exposed to influences reimported from Europe and North America. Consequently there is a good deal of confusion and overlap between the styles as they are now danced - and fusions continue to evolve.
Argentine Tango is danced in an embrace that can vary from very open, in which leader and follower connect at arms length, to very closed, in which the connection is chest-to-chest, or anywhere in between. Close embrace is often associated with the more traditional styles, while open embrace leaves room for many of the embellishments and figures that are associated with Tango Nuevo.
Tango is essentially walking with a partner and the music. Musicality (i.e. dancing appropriately to the emotion and speed of a tango) is an extremely important element of tangoing. A good dancer is one who makes you see the music. Also, dancers generally keep their feet close to the floor as they walk, the ankles and knees brushing as one leg passes the other.
Argentine Tango relies heavily on improvisation; although certain patterns of movement have been codified by instructors over the years as a device to instruct dancers, there is no "basic step." One of the only constants across all Argentine Tango styles, is that the follower will usually be led to alternate feet. Another is that the follower rarely has her weight on both feet at the same time. Argentine tango is a new orientation of couple dancing. As most dances have a rational-pattern which can be predicted by the follower, the ballast of previous perceptions about strict rules has to be thrown overboard and replaced by a real communication contact, creating a direct non-verbal dialogue. A tango is a living act in the moment as it happens.
Argentine Tango is danced counterclockwise around the outside of the dance floor (the "line of dance") and dance "traffic" often segregates into a number of "lanes"; cutting across the middle of the floor is frowned upon. In general, the middle of the floor is where you find either beginners who lack floor navigation skills or people who are performing "showy" figures or patterns that take up more dance floor space. It is acceptable to stop briefly in the line of dance to perform stationary figures, as long as the other dancers are not unduly impeded. The school of thought about this is, if there is open space in front of you, there are likely people waiting behind you. Dancers are expected to respect the other couples on the floor; colliding or even crowding another couple, or stepping on others' feet is to be avoided strenuously. It is considered rude; in addition to possible physical harm rendered, it can be disruptive to a couple's musicality."
And some additions from me. First of all, as I`ve already said, the most prominent Argentine tango composer was Astor Piazzolla, one of my favourite composers.
And some emotional words from the bottom of my heart.
Nothing can be compared to the feeling of a dancer performing tango. Passion, wonderful music, the warmth of your partner`s body, the strenghth of his arms embracing you, love and hatrid, tears and anger, high heels, black dress, serious face... And passion, passion again and all around, the air is hot, agitated and passionate, your breath is hard and hot, your eyes glimpse, your lips burn. You dance and die, revive and kill, fight and win. There are no loosers in this fight. The only loser is the one with tears in his eyes, the one who has no partner to embrace, no enemy to fight with.
Tango is life. Tango is passion. Tango is illness.