Q:

Why do posts not escape HTML characters?

I was re-reading on of my old answers when I noticed that some of it was missing.  Specifically anything which was not in a code block which started with a less then symbol.  Replacing the sysmbol with an &lt; fixed the issue, but why does SO not do this replacement by default?

A:

why does SO not do this replacement by default?

Because Stack Exchange also allows a small subset of HTML. Escaping all HTML characters would display HTML code as text, which is undesired.

