Lines beginning with "R:" indicate a remark (or a comment) explaining the code that follows.

Good comments don't repeat the code or explain it.

The comment explains key terms and concepts, and includes a short signature by the programmer who authored the code.

The singer and guitarist's wryly humble comment explained the cavalcade of guests who appeared throughout the night.

This comment explained why the flowers were appearing in odd places in the border instead of their designated spots.

The admiralty report was not published at the time and official comment did not explain the circumstances.

So 'No comment' and explain why, and the promise of something later.

Your description and the comments above explain in a very large nutshell why I gave up on Lost - it wasn't enjoyable to watch anymore.

Your comment explains precisely why ARM is going to win this format war with Intel.

Your previous comment doesn't explain why it is vital for business.