A domino show is created by standing updominoes in sequence, to create a chain reaction also called the domino effect. Only the first domino should be toppled by hand. Using dominoes of different colors, the builders are able to create patterns and images. The dominoes can have different top and back colours, meaning that the dominoes display different colours before and after being toppled. Other tricks include three-dimensional stackings; shapes such as spirals and letters; Rube Goldberg machines; special toppling techniques, and special effects. The first public domino shows were those of Bob Speca, Jr. from Broomall, PA. In 1976, at the age of 18, he established the first official world record for the most dominos toppled in a chain reaction, by setting up and toppling down 11,111 pieces. That event, and his appearance on The Tonight Show triggered a domino-toppling craze, leading to a long lasting competition among domino-builders about the world record. In 1984, Klaus Friedrich from Germany was the last person to set up a new domino-toppling world record single-handedly. In that same year studentfilm makers Sheri Herman and Bonnie Cutler from Temple University produced and directed a film entitled AND THEY ALL FALL DOWN, showcasing Bob Speca's talents. The film is part of the permanent collection of the . In 1998, the Netherlands hosted a huge domino toppling exhibition called Domino D-Day, it was renamed Domino Day, following the initial 1998 event. It ran annually until 2009, and has been suspended due to financial and administrative issues since 2010. Domino Day made popular the concept of the "Builder's Challenge" where in the build team must place dominoes into the project once the topple has already begun in order to complete the build in a "race against the clock" type challenge. Since 2015, The Incredible Science Machine, an international, multi-team build event has been held annually in the USA, as of November 2017 they hold the current record for most dominoes toppled in America with just under 250,000.
