Are there rules for participating posted somewhere?

I am very new to this site (Day 3). The conversations are quite lively and entertaining. I was directed here from a Google search on bread mold. Thank you for the great answers on that topic. I moved on to several other discussions and finally added an answer/comment of my own. Now I would just like to know more about participating. Specifically, are there spell check or edit functions and how can I comment on a particular post or do all post go to the end of the discussion?