Adding a #pre tag to a text fragment displays the content "as is" and no further formatting will be applied to it (similar to HTML <pre>..</pre> mark-up).

a sample fragment with #pre

Adding both #pre and #code tags to a text fragment displays the content "as is" with program-code syntax highlighting.

a sample fragment with #pre and #code

You can optionally specify the programming language in which the code is written with a #lang-<language name> tag, for more detail of language names, see the google-code-prettify document.