Open Firmware is a standard Forth-based firmware popularized by PowerPC Macs which sees continued use with the OpenBIOS project. Open Firmware was designed to be modular and noticeably easier to port to new architectures compared to other options such as legacy BIOS or UEFI firmware.
Of note, Open Firmware was the system firmware of choice for the ill-fated OLPC XO-1 laptop project. This might have proved Open Firmware's swan song were it not for the efforts of the OpenBIOS community which continues the firmware's development. Largely as a result of their efforts, Open Firmware remains a reasonably common payload for the system initializer Coreboot, allowing anyone to deploy OpenBIOS implementation of Open Firmware on Coreboot supported hardware.
- UEFI — a firmware standard for boot ROM designed to provide a stable API for interacting with system hardware. On x86 it replaced the legacy BIOS.
- BIOS — the firmware of choice for each IBM-compatible PC until a few years ago.
- Coreboot — a free and opensource hardware initializing firmware which supports multiple boot ROM payloads.
- Open Firmware used by the OLPC and others.
- Slimline Open Firmware (SLOF) for virtualized guests on IBM POWER architecture.