What phrase would you use to indicate you are passing along important information?

Using the phrase "FYI" signifies "For Your Information," which is commonly employed to convey important information without requiring immediate action from the recipient. It suggests that the message contains details that may be beneficial or relevant to the recipient, allowing them to be informed about particular matters or updates. This phrase is widely recognized in professional communication, making it a suitable choice for indicating that you are passing along significant information.

The other phrases listed serve different purposes. "ASAP" stands for "As Soon As Possible," indicating urgency rather than merely passing along information. "RTFM" is an acronym for "Read The F***ing Manual," typically used as a sharp reminder to consult documentation instead of asking basic questions. "AFAIK," meaning "As Far As I Know," implies a limitation of knowledge rather than just sharing information. Thus, "FYI" is the most appropriate choice for indicating you are conveying essential information.