An amusement park is a collection of rides and other entertainment attractions assembled for the purpose of entertaining a fairly large group of people. An amusement park is more elaborate than a simple city park or playground and caters for all ages.
Amusement parks evolved in Europe from pleasure gardens, which existed for the recreation of the people, while charging a fee. In the United States, expositions were another influence on the amusement park. Amusement parks were the historical precursors to modern theme parks as well as the more traditional midway arcades and rides at county and state fairs (in the United States). Today, amusement parks have largely been replaced by theme parks, and the two terms are often used interchangeably. The oldest amusement park in the world is Bakken, at Klampenborg, north of Copenhagen, Denmark, which opened in 1583.
Amusement parks collect much of their revenue from admission fees paid by guests attending the park. Other revenue sources include parking fees, food and beverage sales and souvenirs. Some parks charge an entry fee which allows unlimited access to all attractions, whereas others offer free admission but charge guests for each attraction.
A roller coaster inversion is an element of a roller coaster track that turns riders upside-down and then rights them. The degree to which it must invert riders is nebulous and a point of contention when it comes to elements like overbanked turns, which turn riders such that their heads are below their feet, but are not considered inversions.