Do note that those of you that don't properly reply on quotes I do end up editing so you'll see that.
That's called post padding and it will often times make it look like a wall of post.
Basically it'll look like this:
Jen says something
Bob says something
Tom says something
Sara says something
Instead of reply putting in 1 reply with quotes from all 4...they'll do this:
Jim replies and quotes Jen
Jim replies and quotes Bob
Jim replies and quotes Tom
Jim replies and quotes Sara
If I see that, I will edit (but also generally message you as well) so it will appear like this
""
""
""
Sara says something
Jim replies and quotes all 4 in one reply.
Beyond that, yes, Nudielad is correct and only mods and original op can edit their post. The only exception to that rule is if original OP of the topic deletes it, it will delete everything after it as well.