Yahoo! Messenger (sometimes abbreviated to Y!M) was an instant messaging platform developed by Yahoo in the late 1990s. Yahoo! Messenger was shut down on July 17, 2018.

Like early versions of MSN Messenger and Skype, Yahoo! Messenger included a series of shortcode-based graphic emoticons within the platform as far back as its November 2001 version 5.0 update.

Yahoo! Messenger also featured a smiley face mascot similar in appearance to the modern 😀 Grinning Face emoji.