How to post HTML and other code on Blogger

On creating my last post, I encountered a problem - the code I put in the editor was dissapearing, or at least half of it was! I figured this was due to it being read as HTML code, and found from THIS blog post, that you need to use HTML entities instead of normal html tags. I didn't feel too much liek going through my document and changing every tag, so I went searching and found THIS, on the W3C site. You enter HTML code, it converts it to HTML entities ready for posting, easy!