“When I first read the dictionary,” goes an old joke by comedian Steven Wright, “I thought it was a poem about everything.”
Part of what makes that joke funny, of course, is that dictionaries (and glossaries alike) get a bad rap for being nothing but boring old reference material. But boy are they useful when you need them.
Some sites seem to positively cry out for a glossary (i.e. a mini dictionary). And yet those that have them are few and far between.