Cross-platform standard for controlling hardware. Open Firmware is used by all PCI-based computers running the Mac OS.
OpenGL
Industry-standard API for 2D and 3D graphics systems.
open source
Software that is developed, tested, and improved through public collaboration and distributed with the intent that it be shared with others.
ORBS(Open Relay Behavior-Modification System)
A database, accessible via DNS lookups, that tracks known spammers (senders of junk mail). It contains SMTP servers that are known to allow third-party relay; senders of junk mail use these servers to forward their junk mail.