Initialize

Initialize is the action of preparing a system, variable, data structure, or component for use by setting it to a known starting state. Initialization establishes the initial conditions required for correct operation and predictable behavior.

In computer programming, initialization refers to assigning initial values to variables or objects when they are created. It can occur at declaration or through subsequent assignment. Different languages provide various initialization mechanisms, such as direct initialization, copy initialization, or constructor-based initialization.

Common concepts include static or dynamic initialization. Static initialization occurs at compile time or program load and can include zero-initialization, value initialization, or constant initialization. Dynamic initialization happens at runtime, and may be deferred or performed on first use, sometimes combined with lazy initialization to avoid unnecessary work.

Initialization also applies to hardware and software systems during boot or startup. Firmware routines, such as the Power-On Self Test, perform a sequence of initializations to bring memory, registers, and peripherals to a known state before the operating system begins execution.

Improper or missing initialization can lead to undefined behavior, bugs, or security vulnerabilities. Best practices emphasize initializing variables before use, using clear defaults, and documenting initialization requirements to promote reliability and maintainability.

Related terms include zero initialization, default initialization, value initialization, lazy initialization, and bootstrapping.