I've been using StackExchange sites frequently for several months now. However, I'm still baffled as to where to post shell/bash/zsh questions. SuperUser, ServerFault, Unix and Linux, StackOverflow, and AskUbuntu all seem like good candidates.
For example, I want to ask a question about how to see zsh default settings for variables like HISTSIZE and SAVEHIST. On which site do you recommend asking this question?