Haiku is an open source operating system that is compatible with BeOS. Development of Haiku began in 2001 as the OpenBeOS project after BeOS development was discontinued. The first alpha version was released in 2009. Haiku aims to recreate the user interface and functionality of BeOS while improving performance and expanding hardware support. It uses a modular design allowing components to be developed independently. While Haiku strives for compatibility with BeOS, full compatibility is not possible due to changes in compilers and unsupported proprietary APIs. The latest release candidate shows promise with a small footprint and smooth OpenGL performance, though more applications are still needed.