Which of the following is NOT a type of gate?

In the context of gate types, the classification typically includes manual, electrical, and mechanical gates. Manual gates are operated by hand, requiring physical effort to open and close, while electrical gates use an electric motor for operation, allowing for more convenience and security. Mechanical gates, on the other hand, often rely on mechanical components for their operation, which may include gears, levers, or other mechanisms.

Digital, however, does not represent a classification of gate types in this context. While there may be digital elements involved in the control systems of electrical gates, such as digital controls or smart technology, “digital” itself is not a standalone type of gate. Instead, it can be seen more as an enhancement or feature of electronic systems rather than a distinct category on its own. Thus, identifying "digital" as not being a type of gate aligns with standard classifications found in discussions about gate technology.