Initialising

Initialising is the act of preparing something for use by establishing its starting state. This often involves allocating resources, setting initial values, and performing checks to ensure a system can begin operation safely. The spelling “initialising” is common in British English; the American form is “initializing.”

In computing, initialization occurs when a program starts, when variables and data structures are given their first values, or when services are brought online. Variable initialisation assigns a first value at declaration; data structures may be created with a constructor that sets fields. Initialization differs from subsequent assignment, which may change values after the initial setup.

Hardware and embedded systems perform initialization during power-up, including firmware startup, self-tests, clock configuration, memory readiness, and peripheral setup. The goal is to bring all components to a known, valid state before normal operation begins.

Good initialization practice emphasizes determinism and predictability. Steps are often ordered to avoid undefined states, with clear error handling and cleanup paths if a step fails. Some systems use lazy initialization to defer work until it is actually needed, while others favour eager initialization to minimize startup latency.

Etymology traces initialising to the notion of beginning, from Latin initium and related forms. In computing contexts, initialisation is frequently contrasted with finalisation or shutdown, which release resources and conclude processes. Related concepts include bootstrap, startup, and configuration to prepare a system for use.