PACS (Picture Archiving and Communication System) is medical image managing system for purpose of storing, managing, and browsing scanned image data from modality such as CR, CT, MRI, etc.
That means PACS refers to a set of DICOM Server and DICOM Viewer.
In a broad sense, sometimes PACS includes modality, hardware that is installed a system, and other systems such as RIS.
By installing PACS, users can expect a reduction of cost and inconveniences for transporting and preserving films.
Also, integrating with electronic health records, HIS, RIS, and others enables to improve efficiency of hospital work.