https://www.futurelearn.com/courses/shipwrecks/4/steps/60360
stumbled on this and although short and sweet, neatly explains the differences in medieval shipbuilding in Northern and Southern Europe
True. I would have expected to see the word 'cog' near the beginning of the article and the word 'galleon' near the end, but it makes a good introduction.
Here is a replica (https://en.wikipedia.org/wiki/Bremen_cog#/media/File:Ubena_von_Bremen_Kiel2007_1.jpg) of a German cog, showing that in real life these ships may have looked more graceful than the humpy things we see in illustrations.
Another replica (https://upload.wikimedia.org/wikipedia/commons/9/97/Kampener_Kogge.jpg), based on the Kampen cog as opposed to the Bremen. Her proportions are perhaps more like some of the illustrations we have. One noteable thing you get from the picture Patrick shared is how wide cogs were.