Based on the Wikipedia page .
An ice cream soda, float (United Kingdom, Canada, United States, New Zealand, and East Asia), coke float (New Zealand), or spider (New Zealand and Australia) is a beverage that consists of a few scoops of ice cream in either a soft drink or in a mixture of flavored syrup and carbonated water.
The ice cream soda was invented by Robert M. Green in Philadelphia, PA, in 1874 during the one hundred and fiftieth anniversary of the Franklin Institute. The most common story is that on a particularly hot day, Green ran out of ice for the flavored sodas he was selling and used vanilla ice cream from a neighboring vendor to keep his sodas cold. His own account, published in Soda Fountain magazine in 1910, reveals that while operating a soda fountain at the Franklin Institute's one hundred and fiftieth anniversary celebration in Philadelphia in 1874, he wanted to create a new treat to attract customers away from another vendor who had a fancier, bigger soda fountain. After some other tries, he decided to combine ice cream and soda water. During the celebration, he sold vanilla ice cream in soda water and a choice of 16 different flavored syrups. The new treat was a hit, and the beverage's fame spread throughout the country, going even farther later. Its fame made it a fashion among teens to be seen drinking it, although many adults hated it and forbade it on holy days, preferring ice cream sundaes instead, the very name being concocted because it was primarily consumed on the "soda's day of rest". Green's will instructed that "Originator of the Ice Cream Soda" was to be engraved on his tombstone. However, despite this, three other people have claimed to be the creator of ice cream sodas, one of them even being one of Green's employees.
- In some areas, the ice cream soda was considered like alcohol, and as a result was banned on certain days, leaving soda fountain vendors to figure out ways to do business on such days.