ICQ (I Seek You) was one of the very first popular instant messaging (IM) clients. Launched in 1996, it predated AIM, MSN Messenger, and Yahoo! Messenger, establishing itself as a pioneer in the field. Users could exchange text messages in real-time, a novel concept at the time.

While extremely popular in its heyday, ICQ[SQ]s popularity has waned considerably over the years due to the rise of newer, more feature-rich messaging platforms like WhatsApp, Facebook Messenger, and others. While it still exists, its user base is significantly smaller than it once was.

In short, ICQ is a historically significant instant messaging service that[SQ]s largely been superseded by more modern alternatives.