CXC Data Model Manual, Part 1: User Introduction to Filtering and Binning in CIAO

This manual describes the filtering and binning language used throughout the CIAO data analysis package, and some of the basic tools used to do simple analysis tasks. The name ``Data Model'' reflects the intent that there be a high level interface which can be used on data files of different formats: we have a single abstract description (`model') that encompasses all the data files we use. Although the event list, source lists and exposure maps produced as output products from X-ray observations are quite different in their information content, they actually have a lot in common in their underlying structure.