Freestyle , Net , Golf, and Consecutives. You may call it Kick Bag, Kick Sack, Sipa, Hack, or something else. Hacky Sack is a brand name of one type of footbag, and because it was the first to hit the mass market, it's brand name is strongly recognized.
Today there are many different brands on the market.
The CFA manufactures an assorted line for beginners and pros alike. Hackin' the sack originated in Oregon City, Oregon in 1972 with the basic game being to keep the footbag aloft using only the feet and knees. The current Guinness World Record for consecutive kicks is 63,326 without a drop. Through the years this very simple game has grown to be a full fledged sport with Freestyle , Net , Golf , and Consecutive events. Tournaments are held all around the world where athletes compete for cash and prizes.