The cha-cha is a dance that began in North America and is based on music and dance brought from South American migration to the U.S., especially New York. Its a mixture of several musical styles from different parts of the world, with a large part of the influence being from jazz. The dance first became popular in the United States around the mid 1950s.
It is a sibling of the mambo, which evolved into the triple-mambo and then the cha-cha. It was initially known as the cha-cha-cha and then as time went on the name was shortened. The name came from the noise that people's shoes would make when dancing, and from the maracás used in the dance. It is now one of the most popular Latin dances in the United States.