DiRAC  is the integrated supercomputing facility for theoretical modelling and HPC-based research in particle physics, astronomy and cosmology, areas in which the UK is world-leading.

In 2009, the Science and Technology Facilities Council (STFC) received £12.32 milllion, from the Government's Large Facilities Capital Fund to invest in new hardware to provide UK particle physics and astronomers with upgraded HPC technology to address some of the most challenging scientific problems. In 2011, DiRAC received an additional £15 million from government (DiRAC II), together with a contribution towards operating costs from STFC.

DiRAC provides a variety of computer architectures, matching machine architecture to the algorithm design and requirements of the research problems to be solved. There are sound scientific reasons for this choice which was adopted as a philosophy following a number of in-depth reviews involving the research community which gave detailed advice on the nature and balance of resources required by the STFC research community. The demands of the different research domains supported by STFC are such that a distributed installation was the most cost effective way to satisfy the varied scientific requirements.

As a single Facility, DiRAC allows more effective and efficient use of equipment, promotes the science goals of the STFC communities, provides a common training and consultation framework and, crucially, provides critical mass and a coordinating structure for both small and large scale cross-discipline science projects, the technical support needed to run and develop a distributed HPC service, and potential knowledge transfer and industrial partnership projects. The continued pooling of complementary expertise will ensure that the UK remains one of the world-leaders of theoretical modeling in particle physics, astronomy and cosmology.