Balloons are made from a liquid rubber called latex. In the factory, color is added to the latex so that we can have all colors of balloons. Natural rubber latex comes from the sap of the rubber tree. The tree grows in Malaysia and its sap is collected there and then shipped to the U.S. on large ships.

Regular balloons are made of latex which is a type of rubber. Here is a nice web site that describes the process (with pictures!): click here for balloons.