What is the difference between regular dots and polka dots do Polka dots have anything do to with the dance the Polka?

The difference does seem to be related to the dance. While regular dots have been used in clothing, 'polka dots' tend to be larger, and used for informal attire. Because the popularity of the Polka dance and the popularity of the larger-dotted fabric occurred within the same time period - about the later 1800s - the pattern was named 'Polka dot'.

https://en.wikipedia.org/wiki/Polka_dots
http://ezinearticles.com/?History-of-Polka-Dots&id=5696782
https://en.wikipedia.org/wiki/Polka