I have learned that given a Dynkin diagram corresponding to a Kac-Moody algebra, I should be able to use the diagram to read off the generators and relations of the Weyl group of that algebra. Each node should correspond to a generator of order 2, and the number of edges between nodes g and h (or a lack thereof) should tell me something about the order of gh.
However, I can't seem to find a consistent answer about how to interpret the numbers of edges that I see. For example, Wikipedia has some edges marked with an infinity symbol, while Kac's Infinite Dimensional Lie Algebras doesn't seem to use this at all. I have come to the conclusion that maybe the conventions are different in Lie theory, but I'm not sure about this. If anyone can refer me to a book which explains how to use Dynkin diagrams to get the Weyl group, that would be amazing.
