dp.SyntaxHighlighter – free javascript syntax highlighting
dp.SyntaxHighlighter is a free javascript tool for source code syntax highlighting.
The script is meant to help a developer to post code snippets online with ease and without having to worry about applying format. People who use blogs like MovableType, .Text (dotText), dasBlog and any other system can easily add code to their posts.
This seems to be the source code highlighter used also in Yahoo API documentation