Subcomponent

Subcomponent refers to a component that is part of a larger component. It is a discrete unit with a defined interface and a specific role within the parent component. Subcomponents enable hierarchical design, modularity, and reuse by allowing complex systems to be built from smaller, independently developed parts.

In hardware and electronics, subcomponents are the individual parts inside an assembly or module, such as a power regulator, sensor interface, or memory block within a microcontroller board. These parts may be integrated on a printed circuit board or embedded within a housing. Subcomponents expose interfaces to the outer component and can often be swapped or upgraded without redesigning the whole system.

In software, subcomponents are smaller software units that compose a larger component, such as modules, services, or libraries that collectively implement a component's functionality. They communicate through defined interfaces, and their internal implementations are typically encapsulated. The term is common in component-based software engineering and in microservices architectures where a component is built from multiple services or modules.

Design considerations include defining stable interfaces, managing dependencies, and ensuring compatibility across versions. Proper encapsulation reduces coupling and supports testing, maintenance, and replacement of subcomponents without impacting the entire component.

Lifecycle and evolution: subcomponents may be developed, tested, and released independently, then integrated. Changes to a subcomponent can necessitate interface contracts or integration testing for the parent component. See also: component, module, interface, system architecture.