Why a can of worm?  First off not all cameras offer a choice and you maybe stuck with JPG ; then it becomes a matter of camera use and finally it is a matter of opinion more than anything else.
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While I am a firm advocate of the raw format I must recognize that it has its uses in some type of photography that require relatively long bursts of shooting captures.  (If it last more than a few secondes, buy a video camera!!!)
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Then there are opinons that are, well, a bit too extreme and an excuse to produce GES.  'If it is on the web it must be true' prevails. Anybody and his sick brother can promote any point of view without verification. Folks who read this type of information and take it to heart are responsible for the GES I always attack.  These folks feel personally threatened with some reason when their beliefs are challenged after all who wants to be made a fool of?  And so it becomes a matter of faith. We have not landed on the moon after all and 'Elvis lives!'.  One of the annoying aspect of the human beast.
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Personnally I consider that any photographer who wants to produce quality work and enter the 'fine art' section of producing photographs must use the best cameras can offer when selecting a file format.  That format is 'raw'.
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raw does not stand for anything other than raw, like raw meat, unprocessed, untouched, uncut and of course unspoiled.
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JPG 'users' accuse raw shooter to use raw to correct their mistakes.  This accusation does not stand scrutiny if you ever take that statement to heart.  GES producers do not use raw to start with so where does this leave us?  Nevermind, do not answer that.
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So, what is raw in layman's term?  raw is the straight recording of what the sensor saw when a capture is made.  This recording is not an image but a latent one a bit like a 'digital negative'.  What the sensor records is basic:  Focus (DOF), luminosity and whatever light artifacts due to the sensor weaknesses (including dust bunnies).   A raw file records all the camera settings like focus point, color balance used, flash and whatever else the camera registers.
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raw files have the reputation to be dull looking, not anymore.  The change is simply due to the integration of a JPG file within the file.  Most image readers access the JPG and ignore the 'real thing' making the display more attractive but highly innacurate.
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raw is usually uncompressed.  When compressed raw is lossless.
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Now that I described a raw file I have to describe a JPG, just to be fair (ah!)
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Then there is sraw for 'small raw'.  That thing was rightly described as 'the evil cross between a raw file and a JPG'.  It retains most of a raw file structure but uses the averaging of four pixels to create one.  Not only the image is reduced in size (both as files space and print size) but it also messes with both color accuracy and luminosity (averaging thingy you know).
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A JPG is a camera processed capture that reduces the dynamic range and color depth of a capture.  JPG file use a cumulative lossy compression meaning that each time you OPEN
AND
SAVE a JPG you add to the loss.  One of the most noticeable flaw of a JPG capture is the banding created when a relativey large area is made of gradual changes in color like a blue sky.  JPG compression is controlable from extreme to almost none.  JPG excels with detailed captures but then the compression is not as effective.
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The method of compression w/o entering too many details is simple, adjancent pixels are sampled and if similer thay are averaged and bundled together creating 'clumps'.  The sampling that takes place determines the compression quality and ultimately the capture quality.  The wider the sampling the smaller the file size and the greater the artifacts distortion due to compression.
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I will add a side by side comparison soon as well as samples of JPG banding and artifacts.