Yes, WSG is white smooth glossy, and it came in several contrast grades, which basically means that each grade allowed you to print making a variety of different contrast 'look's on each grade, just by altering the combination of exposure time and development time. For a 'normal' negative, one that is neither over- nor underexposed, nor over- or underdeveloped, grade 2 was the usual choice that would allow you to get the widest range of tones from that negative.
If your negative, for whatever reason, was too contrasty, you'd drop a grade and from 2, go down to 1. The opposite was also true: if your negative was too flat - not enough contrast in it - you'd go up the grades to grade 3 or above. You'd also choose to use different grades not because you had a bad negative, but because you simply wanted to accentuate contrast or do the opposite. Quite flexible, it was! In reality, I only stocked grades 2 and 3 because they coped with pretty much anything.
WSG could be air dried or drum dried or just dried off (if you were poor) on a flatbed glazer, a heated box-like thing that came with a thin sheet of very polished stainless steel or chrome plated steel. The wet print would be squeegeed on a sheet of perspex to get rid of excess water from the washing bath, and then placed face down onto the shiny steel plate, and a roller would be used to get rid of any air bubbles between paper and sheet (glazing sheet, it was called) and then this combined thing would be placed onto the box, metal sheet against box, and a fabric curtain pulled up from the back of the box so as to tightly bind the paper and sheet together during the heating/drying process. If you were lucky and a meticulous worker, when the print felt dry though the fabric curtain, you would release the pressure of said curtain and remove the print, now flat and super-shiny. If not so fortunate, parts of the print could appear stuck to the plate, and your troubles would be just beginning. If instead of placing the print face down onto the plate you put it in contact the other way around, you would end up with what was known as unglazed WSG. Depending on the quality of the 'curtain' your dried print would then either have fluff glued to it or be perfectly fine.
This latter state of final print was preferred by reproduction houses because it made their life more easy because it offered less reflections when being copied on their process cameras. Of course, being a selfish bugger, I didn't give a damn and always gave my clients a highly glazed print because it looked better that way. Why, I felt, should I do the repro house's work for it and, in the process, appear to be handing over a second-class print?
If you were the lucky owner of a drum glazer, it signified you were doing very well! It also allowed you to feed in prints for drying as if on an endless belt, if the rotation speed wasn't too high for the drying process, when you'd get still stuck prints about to go round a second time. If partly dry, they could foul against the pressure curtain (blanket) and crease, demanding a reprint. If you had any large output of prints, this was an essential piece of production kit. It also seemed to be more reliable than flatbed drying with far less sticking. To avoid sticking, some of us passed the print through a bath of wetting agent prior to making the plate/print contact, but in my view, I think accidents were more often due to dirt getting into the sandwich, or insufficient washing. The great thing about these rare disasters was that you really never could tell what had gone wrong to cause them: it just did. Great fun, and character-forming.
Getting WSG-like digital prints from desktop printers was never successful for me. My good printer was an HP B 9180 that used pigment inks; I believe that you should use dye-based inks for glossy digital printing? The test-runs for that HP were done using a gloss paper and it looked great; however, as I did mostly b/whites, I ran into the problem of bronzing when using the gloss paper and just had to give up and revert to matt surfaces that looked great behind glass or within archival sheaths, both providing faux glossiness that looked beautiful.
;-)
Rob