Acronyms, abbreviations and definitions of terms
================================================

For clarity this section gathers all the relevant shortcuts that will be used in this document.

Acronyms
--------

.. glossary::

   :abbr:`DPDD (Data Product Description Document)`
	 The Data Product Description Document - This document

   :abbr:`DPS (Data Processing System)`
	 Data Processing System

   :abbr:`EAS (Euclid Archive System)`
	 Euclid Archive System

   :abbr:`ECSGS (part of the Science Ground Segment c/o the Euclid Consortium)`
      part of the Science Ground Segment c/o the Euclid Consortium

   :abbr:`ECSURV (Euclid Consortium Survey Group)`
      Euclid Consortium Survey Group
      
   :abbr:`ESA (European Space Agency)`
      European Space Agency

   :abbr:`MEF (Multi-Extension FITS)`
      Multi-Extension FITS

   :abbr:`MOC (Mission Operations Center)`
      Mission Operations Center

   :abbr:`OU (Organization Unit)`
      Organization Unit

   :abbr:`PA (Product Assurance)`
      Product Assurance

   :abbr:`PE (Processing Element)`
      Processing Element

   :abbr:`PF (Processing Function)`
      Processing Function

   :abbr:`PK (Power Spectrum)`
      Power Spectrum Processing Function

   :abbr:`SAS (Science Archive System)`
      Science Archive System

   :abbr:`SOC (Science Operations Center)`
      Science Operations Center

   :abbr:`SDC (Science Data Center)`
      Science Data Center

   :abbr:`SGS (Science Ground Segment)`
      Science Ground Segment
      
   :abbr:`SWG (Science Working Group)`
      Science Working Group

   :abbr:`UML (Unified Modelling Language)`
      Unified Modelling Language

   :abbr:`WP (Work Package)`
      Work Package

   :abbr:`2PCF (Two Point Correlation Function)`
      Two Point Correlation Function

   :abbr:`3PCF (Three Point Correlation Function)`
      Three Point Correlation Function


Abbreviations
-------------

.. glossary::

   :abbr:`SVN (Apache subVersioN)`
      Apache SubVersioN

   :abbr:`Git (Global Information Tracker)`
      Global Information Tracker

Definitions
-----------

.. glossary::

   Mission Data Base
      A data base maintained in the Euclid Archive Systems that contains reference information on
      the mission, spacecraft, instruments, survey, sky, that is of interest for the data processing
      sector of the SGS. Processing Functions interface with the Mission Data Base for this
      information so that we can maintain a clear control over the parameters of the system that
      enter data processing. Typical examples of MDB elements are the filter transmission curves,
      the Galactic extinction map, the telescope optical properties...

   Processing Function
      Represents self-contained processing parts (i.e. doing tasks); PFs constitute the first step for
      the realization of a distributed pipeline development, i.e. they are the result of the highest-level
      breakdown of the complete pipeline (scientific data processing) that can be achieved with
      components that communicate only with the help of the Euclid Archive System (EAS).

   Processing Element
      An atomic block of a PF. It inputs and outputs data, and cannot be split further from the
      functional point of view. A PE may completely meet several functions or features. Each
      processing Element may be broken down into software components.

   Pipeline
      A composition of one or several Processing Elements coming from the same Processing Function
      or from different PFs. PEs composing a pipeline are chained by associating output data of one
      or several PEs to input data of one or several PEs. It contains therefore inputs and outputs
      data itself. Intermediate data (interfaces between PEs of the Pipeline) may or may not be input
      or output data of the Pipeline. A processing function (PF) may be composed of one or several
      Pipelines.

   Science Data Center
      A national supercomputing center, where the actual data processing for Euclid will be carried
      out. Processing for Euclid is distributed on a network of SDCs, and an initial node, residing
      at SOC orchestrate the processing to adjust the load to the availability of resources.

   Software Component
      Term to indicate a generic piece of software resulting from the software breakdown process.
      The “software component” term can be used to speak of a software product, or of an indivisible
      program or library, or of a software module, or of a software unit, depending on the level at
      which the considered software components lays in the software breakdown hierarchy.

*Extend further as required per this document.*