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The word “survey” in the astronomical context initially referred to what could be called a sky atlas - these were initially hand-drawn sky charts, and later photographic images. Currently the word survey largely denotes catalogues of astronomical sources and their properties (positions, fluxes, morphology, etc.). They are used to systematically map the universe and characterize its astrophysical components with the aim of discovering new types of objects or phenomena. Surveys are often preceded by the development and introduction of new technology. Where the technological advancement allows us to observe the sky in some new way, for example, viewing images in a previously unexplored wavelength range. The Sloan Digital Sky Survey (SDSS) is one such astronomical sky survey.  The SDSS is a five-filter imaging survey consisting mostly of the Northern Galactic Cap combined with a spectroscopic follow-up program. The survey and its extensions (SDSS-II and SDSS-III) cover approximately〖〖14 500〗degrees〗^2, which is nearly a third of the entire sky. SDSS’ main telescope is at Apache Point, New Mexico, and it is was specially designed to take wide field (3°×3°) images using a mosaic of thirty 2048×2048 pixel CCDs\cite{Djorgovski_2013}. The survey includes a spectroscopic survey of approximately 1.3 million objects — mostly galaxies, and quasars.   SDSS's most used data products are imaging, and spectroscopy. Image parameters measured for each object  include positions, fluxes, the position, flux,  and morphology of detected objects.The the object.The  spectroscopic parameters include redshift, and spectral classification. The number of objects loaded in the databases, observing conditions for imaging fields and for spectroscopic plates, and other parameters are included in the data products. \cite{Stoughton_2002}  Parameters used for imaging or spectroscopy (respectively), are grouped into classes. Table X (table of parameters of \cite{Stoughton_2002}. Optical data in particular helps to establish  the SDSS) indicates some of source's distance and to classify  the parameters associated with imaging data, their type/ class object. Source mophology on the other hand helps to identify emission mechanisms  and gives a description properties  of each parameter. the media surrounding our objects. (http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1995ApJ...450..559B&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf)  \subsubsection{Faint Images of the Radio Sky (FIRST)}