On a discord, trying to explain Classic Traveller to D&D people:
So Classic Traveller is like Original D&D. It started as 3 small books that give enough to be a game, but with a lot of unanswered questions. So each supplement adds a little something new, either new rules or expanding the setting or both. But instead of making a few supplements and then combining and revising and unifying it to make B/X, you just add hundreds of supplements for 10 years.



