Anyone and everyone can edit discussion pages on the wiki (sometimes called talk pages).
However, the basic rules of common courtesy apply - polite disagreement is always welcome (especially when it brings to light evidence that has been overlooked or mistakenly identified!); abuse is not. They shouldn't need to be spelled out further than this, and nor should the consequences of failing to follow them.
You should also:
- consider setting up an account so that you can be identified as you, particularly if you contribute regularly
- if you have an account, end each comment on a discussion page by hitting tilde (~) three or four times to sign your name (thus - +Wiglaf (talk)) or name and datestamp (thus - +Wiglaf (talk) 10:10, 7 March 2015 (UTC))
- if you don't have an account, sign manually to signify the end of your comment
Registered users each have their own page, which can be accessed by following their signature. This can be a chance them to give information about themselves, a place to continue a discussion away from a specific article's talk page, or somewhere for you to experiment with formatting techniques without making a mess of a "real" page. Try mine above if you like.
It's also polite to sign if you make a change to another user's page, so its clear what they've put there themself and what has been done by others. If they like it they can always delete the signature and accept it as part of what they want to say about themselves (or delete it entirely if they don't like it!).