Switching

Switching refers to the process of changing from one state, condition, or pathway to another. The term is used across disciplines to describe control or selection mechanisms that direct energy, information, or behavior along alternative routes or states.

In electrical engineering, switching involves turning electrical currents on and off or redirecting them through different circuits. Switching devices include transistors, diodes, and relays. High-frequency switching underpins switching power supplies and DC-DC converters, using techniques such as pulse-width modulation to regulate output while minimizing losses and heat.

In data communications and computer networks, switching determines how data packets or frames are forwarded between devices. Circuit switching establishes a dedicated path for a call; packet switching shares network links, with routing decisions made at each hop; store-and-forward and cut-through are common switching methods in packet switches.

In cognitive psychology and human factors, task switching describes the ability to shift attention and control between tasks. Switch costs reflect slower performance and increased errors when switching, influenced by factors such as task similarity, preparation time, and cognitive load, with implications for interface design and multitasking performance.

In linguistics, code-switching is the practice of alternating between languages or varieties within a discourse. It serves social, contextual, and pragmatic functions and is studied as a marker of identity, proficiency, and community norms.

In biology and systems biology, gene expression can exhibit switching behavior, where regulatory networks toggle genes between active and inactive states. Bistable switches and feedback loops underpin processes such as cell differentiation and developmental decision making.