proximity

Proximity refers to nearness or closeness in space, time, or relationship. It is a general concept used across disciplines to describe how near one thing is to another, or how closely related two things are. Proximity can be measured in physical distance, but perceived proximity can differ based on context, perception, or purpose.

In psychology and design, proximity is a Gestalt principle stating that elements placed close to each other are perceived as a group or a related unit. This principle guides layout, typography, and user interfaces to convey structure and improve readability by visually grouping related items.

In geography and urban planning, proximity is a core factor in accessibility. Proximity analysis uses distance to locations such as housing, schools, or services to assess potential usage or equity. Tools include geographic information systems that compute near-ness and travel times.

In engineering and technology, proximity effects describe how neighboring objects influence a signal or field. Proximity sensors detect the presence or distance of nearby objects without physical contact, using capacitive, inductive, or infrared methods.

In marketing and communications, proximity marketing or location-based services deliver messages or offers to users in close physical proximity, often via Bluetooth, NFC, or Wi‑Fi.

In mathematics and topology, proximity describes a relation that captures the idea of closeness between sets without requiring a metric, enabling analysis of continuity and convergence in more abstract spaces.