As its name implies, a slide gate either slides on wheels from left to right or right to left, not unlike many department store automatic doors.
Slide gate operators are commonly installed at the end of the gate in the closed position but can also be installed by the end of the gate in the open position. In America the most common form of automation is a chain attached across the gate near the bottom and passing through the operator, which shuttles it back and forth.
In the end of the gate/open position you do not see the chain or any operating equipment near the gate. In Europe a metal or plastic rack is attached to the gate with a gear fitted to the operator. The American method is more flexible and allows for greater movement in the gates, the European method makes for a quieter and more secure system. Sliding gates are often large, heavy and therefore more hazardous than swing gates they can however be equipped with appropriate safety devices making them some of the safest gate systems available.