how do you delete posts?
Generally, the only people who can delete posts (even their own) are mentors and admins. Generally, we delete posts on poster request only for stuff that we would have deleted anyway ("oops, I posted that before I realized it should have gone in the homework forums, and now I've re-posted there so can you delete this one?"), and for unusual or serious circumstances like privacy or legal issues.
In such cases the thing to do is hit the "Report" button on a post, which sends a message that all the mentors and admins can see. Explain why you want the post deleted. If we need to get back to you about it, we'll PM you.
I can delete my own posts by clicking Edit, then Advanced, then Delete. But why do some of my posts have "Edit" buttons and some don't?
I forgot, regular members do have the ability to edit and delete their posts for a limited time after posting. I think it's something like one hour. (Or did we change that again? We've changed the policy once or twice, that I remember.)
I think it's 24 hours now.
More explanation of the "edit window". If you make a post, then read it and find you made an error or noticed it is in the wrong thread/forum, the "edit window" allows you to correct the situation. The reason we do not allow unlimited edit time is that some unscrupulous people will go back and change or delete posts long after they have posted them, which can destroy the continuity of discussions or be used for the purpose of deception.
Its a nice feature. Sometimes our inner idiot emerges and we need to rethink it. 24 hours is enough.
Separate names with a comma.