Hi @Rubyupbeat!
I know what you mean - it can be so frustrating when you've typed something out and you hit 'Post', just as you spot a spelling or grammatical error! Unless you immediately type another message apologising for/explaining your mistake, you're almost certain to receive an onslaught of responses pointing out your oversight! It would be great if we could quickly do a 'ninja edit', or if there was an auto-spellcheck before something is posted.
However, I understand why this isn't an option - it's because people will obviously read what you've written and respond to it. If you were to then go back and alter your original message, the rest of the thread my cease to make sense, or it could make other posters look like they've not understood your post/like they're over-reacting/being antagonistic.
For example:
Your original post could say "I love football and support Manchester United - they're the best! But DH hates the game and won't let me watch it and takes the plug off the TV when I want to watch a match. AIBU? Or is he?"
Then, another Poster could reply: "I love football too, but you're wrong about MANU being the best; everyone knows it's Arsenal! I think your DH is BU - that's borderline abusive, is he always this controlling? Talk to [DV Helpline Phone No.] for help."
If you were able to edit your post, you could change it to: "I love football and support Arsenal - they're the best! But DH supports Liverpool and today he told me that he thinks Liverpool are better than Arsenal. I was so upset that I cried for 3 hours, then I took his Liverpool shirt and poured bleach on it. AIBU? Or is he?"
So you can see how this would make the other poster's comment look a bit bonkers!
I use Reddit quite a lot and they have a system whereby you can edit replies (but not the original post - so on Mumsnet, this would obviously be your first post where you've asked your question), but once you have made a change to your post, it is marked so that others can clearly see it has been edited since it was originally posted. Reddit users, when they have made an edit to their post, tend to add a line to the bottom of the text explaining what they've changed. E.g. "EDIT: Corrected a spelling mistake" or "EDIT: Added a link for additional information for those asking."
So there are pros and cons to being able to edit a post. In terms of deleting posts though - that's an easy one! All you need to do is click on 'Report' on the top right-hand side of a post and ask MNHQ to delete it for you, and voila!
p.s. Thank you for your lovely comment on another post!