Simplify the following text for a Grade 14 native English-speaking person.
Original: Such promotions are Jersey All Pro Wrestling , , Lucha Libre USA , , World Xtreme Wrestling , CHIKARA , Combat Zone Wrestling , Elite Wrestling Riot , Heartland Wrestling Association , Maryland Championship Wrestling , Memphis Wrestling , New York Wrestling Connection , Pier 6 Wrestling , Chaotic Wrestling , Next Era Wrestling , ULTIMATE WRESTLING , East Coast Wrestling Alliance , Ohio Valley Wrestling , Pro Wrestling Guerrilla , Ring of Honor and its sister promotions Full Impact Pro and SHIMMER Women Athletes .
Simplified: In pro wrestling , the independent circuit or indy circuit refers to the many wrestling shows that are much smaller than major wrestling companies , like World Wrestling Entertainment ( WWE ) and Total Nonstop Action Wrestling ( TNA ) .