keil

Keil is a term with several related meanings. In German, keil (lowercase) refers to a wedge—a tapered block used to split, secure, or align components in mechanical work. The word is also used in engineering and construction to describe devices that perform these functions, and it appears in various German proper nouns and place names.

As a surname, Keil is of German origin and is borne by individuals across different fields and regions. The name has been associated with figures in science, academia, and the arts, among others.

The most widely known modern reference is Keil Elektronik, a German company that developed embedded software tools. Under the Keil Software brand, the company produced popular development environments and compilers for microcontrollers, notably the μVision integrated development environment (IDE) and toolchains for architectures such as 8051, C166, and ARM. Keil’s workflow and documentation helped many engineers write, debug, and optimize code for constrained embedded systems.

In 2005, ARM Holdings acquired Keil Elektronik, incorporating its tools into the ARM development ecosystem. Since then, Keil-branded tools have been marketed as part of the ARM MDK (Microcontroller Development Kit) for ARM Cortex-M based microcontrollers, providing a complete environment that includes the μVision IDE, ARM compilers, debuggers, and middleware integration. Keil tools remain widely used in education, prototyping, and professional embedded-system development, especially for ARM-based devices.