Introduction.tex

The NeXus file format for neutron, X-ray, and muon science data arose out of a desire to record data in a way that is ``facility-neutral". Recent changes to the format allow storing a full description of the instrument geometry, however users have so far not had a straightforward way to update geometry or other complex details which may change on an experiment to experiment basis. The NeXus Constructor, a tool being developed by software developers based at ISIS Pulsed Muon and Neutron Source in the UK and the European Spallation Source (ESS) in Sweden, attempts to address this problem by providing a graphical interface for scientists to easily construct, modify and visualise the contents of NeXus files.