loader

A loader is a device or program that performs the action of loading something into a system for use. In mechanical terms, loaders are equipment used in logistics, construction, and agriculture to move, lift, or place material. Common types include front-end loaders (wheel loaders) and skid-steer loaders, often equipped with buckets; forklifts serve similar purposes for pallets. These machines transfer material from one location to another, typically onto trucks, conveyors, or storage areas.

In computing, a loader refers to software that loads data or code into memory. A boot loader starts the startup sequence by initializing hardware, locating and loading the operating system kernel from storage into memory, and transferring control to it. Popular boot loaders include GRUB and Windows Boot Manager. Dynamic loaders, or run-time linkers, load shared libraries needed by a program, perform symbol resolution and relocation, and may support lazy binding. The loader typically runs as part of the operating system or runtime environment and works with the linker to prepare an executable for execution.

Other uses include data loaders in databases or ETL workflows, which extract data from sources, transform it, and load it into target storage. The term is sometimes used broadly to denote any component that prepares data or code for use by a system. In practice, the terms loader, linker, and boot loader describe related but distinct roles in preparation, loading, and execution.