Waltz
This "mother of all dances"originated in Italy in the 1600's as a round dance called the Volte. It arrived in America in the early 1800's and was the first social dance in which a woman was actually held in a man's arms. Learning to Waltz is elegant. The Waltz develops "graceful movement" and "poise". Every wedding reception, social "black-tie" formal and holiday party includes Waltz steps.
Tango
Rudolph Valentino single-handedly danced this Latin import in nationwide popularity beginning in 1910. Although widely believed to have originated in Argentina, it actually may have come from Spain. It's dramatic, exciting and is known as the "Dancer's Dance". the Tango with all its staccato movements, greatly improves a man's lead or a woman's ability to follow (respond) and develops a "strong sense of feeling" for music.
Fox Trot
Created in 1912 by Harry Fox, the Fox Trot was the first dance that permitted people to hold each other closer than arm's length. If you think the term "dirty dancing" was a product of the '80s, think again. The Fox Trot was at first to be tagged "indecent behavior". Today it's still the most popular of all social dances. Some people refer to the Fox Trot as the "Slow Dance" or the "Two-Step", or a "Conversational Dance" because of it's closeness and conversation ability at the same time. The Fox Trot is good for developing "smoothness" and "ease of movement".