Firmware

Firmware is software stored in a device’s nonvolatile memory that provides low-level control of its hardware and basic operating functions. It bridges hardware and higher-level software, often starting the device and managing its components.

Bootloader: A small program that loads or selects an operating system or other software during startup. It is often the firmware stage that hands control to the operating system.
Embedded system: A computer system built into a larger device to perform dedicated functions. Firmware is a defining software layer in many embedded systems.
Firmware update: A process that replaces or modifies software stored in a device’s firmware memory. Updates can add features, fix defects, or change hardware behavior after sale.
Application software: Software designed to help users perform specific tasks, such as editing documents or browsing the web. Unlike firmware, it typically runs above the operating system and is not responsible for basic hardware control.
Basic Input/Output System: Legacy PC firmware that initializes hardware and begins the boot process. It shows how firmware prepares a computer before its operating system runs.
Router: A networking device that forwards data packets between computer networks. Its firmware implements routing, network services, and configuration controls.
Over-the-air update: A wireless delivery of software updates to a remote device. It lets manufacturers update firmware without a physical connection.
Operating system: System software that manages computer resources and provides services to applications. Firmware starts or supports the platform; the operating system manages it at a higher level.
UEFI: A modern firmware interface that initializes computer hardware and provides services for booting an operating system. It is the prevalent successor to the PC BIOS and defines a richer boot environment.
Solid-state drive: A data-storage device that uses flash memory rather than spinning disks. Its firmware manages flash translation, error correction, and wear.

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