An escalator is a moving staircase with steps that move up or down using a conveyor belt and tracks that keep the steps horizontal, and is common in airports, train stations, hotels and department stores.
However, it was initially intended to provide fun, not transport. The first patent relating to an escalator-like machine was granted in 1859 to Jesse Reno for a steam-powered moving stairway or "inclined elevator." In 1895, Reno created a novelty ride at Coney Island from his design, and he founded the Reno Electric Stairways and Conveyors company in 1902.
The escalator as we know it was later re-designed by Charles Seeberger in 1897, who created the name "escalator" from the word "scala," which is Latin for steps and the word "elevator," which had already been invented.
Seeberger worked with the Otis Elevator Company to produce the first commercial escalator in 1899 at the Otis factory in Yonkers, NY. The Seeberger-Otis wooden escalator won first prize at the Paris 1900 Exposition Universelle in France.
Charles Seeberger sold his patent rights for the escalator to the Otis Elevator Company in 1910. Otis also bought Jesse Reno's escalator patent in 1911.
In the 1920s, Otis engineers combined and improved the Jesse Reno and Charles Seeberger escalator designs, and created the cleated, level steps of the modern escalator in use today. Over the years, Otis dominated the escalator business, but lost the product's trademark. The word escalator lost its proprietary status and its capital "e" in 1950 when the US Patent Office ruled that the word "escalator" had become just a common descriptive term for moving stairways." (info from Otis and About.com)
Download escalator history & technology brochure from Otis