Hi All, I'm new to logback, I've read a good part of the documentation, and first I should said that I'm impressed by the quality of the documentation and the feature rich logging system you provide. Two things: Question: I have trouble to understand what is a Marker and what is the use case behind them. Could you give me some insight? Remark: While reading the documentation I had the feeling that MDC was introduced too late. Indeed, you reference MDC the first time in chapter 2 (as far as I can say), without giving even an hint on what it is. Several other chapters reference this concept, but it's only in chapter 7 that I understood what it is. Maybe adding a short introduction to this concept (and the concept of Marker) in chapter 2 would help the reader? Thanks for your great work! Xavier