Waist-high
Sometimes also referred to as "half-height" turnstiles, this fixed arm style has traditionally been the most popular type of turnstile. There are many variations of this style available, including one which is designed to be accompanied by a matching ticket box, and one with a ticket box built in. Some styles are designed to allow entry only after a payment (actual coins and tokens) are inserted, while others allow access after a valid barcode is electronically read.
Optical
Optical turnstiles are an alternative to the traditional "arm"-style turnstile and are increasingly used in locations where a physical barrier is deemed unnecessary or unaesthetic. Optical turnstiles generally use an infrared beam to count patrons and recognize anyone attempting to enter a site without a valid entry pass.
HEET turnstile
Full-height turnstiles
The High Entrance/Exit Turnstile (HEET), or full-height turnstile, is a larger version of the turnstile, commonly 7-foot (2.1 m) high, similar in operation to a revolving door, which eliminates the possibility (inherent in the waist-high style) of anyone jumping over a turnstile unit. It is also known as an "iron maiden", after the medieval torture device of the same name, or as "high-wheel".[1] It is sometimes called a "Rotogate", especially in Chicago, where it is used at unstaffed exits of Chicago 'L' stations, and is also used at many New York City Subway stations, where it is called a HEET. In Europe, however, "Rotogate" refers to a different kind of gate that is not a turnstile.