gate

Gate is a term with several related meanings across different contexts. In architecture and everyday use, a gate is a movable barrier set at an opening in a fence, wall, or enclosure. Gates are typically hinged or mounted on a track and can swing, slide, or rotate. They are operated by a latch, lock, or handle and made from materials such as wood, metal, or composite. Their purposes include controlling access, providing security, and marking boundaries.

In historical and urban settings, city gates were integral to fortifications and town planning. They served as controlled entry points and could be reinforced with features such as towers, portcullises, and drawbridges. In modern use, gates mark property boundaries or serve as entrances to driveways, gardens, or courtyards. In transportation hubs, a gate denotes a boarding point where passengers begin their journey, for example at airports or ferry terminals.

In electronics and computing, a logic gate is a basic building block that produces a binary output from one or more binary inputs. Common types include AND, OR, NOT, and XOR gates, and they are combined in circuits to perform complex processing. The term gate also appears in transistor technology as the gate electrode that controls current flow in a field-effect transistor.

The suffix -gate is used in media and public discourse to denote a scandal or controversy, a usage that originated with the Watergate affair and has since become a general convention.