Messenger, and MSN Messenger.
… Do you still remember your UIN?
Users were issued a unique User Identification Number, or UIN, upon registration.

The coming decade would again reinvent personal communication, driving conversations from mouse and keyboard to mobile devices.
The ICQ mobile app was last made available through Huawei’s AppGallery before it was retired.
It also included smart replies and autofill, similar to the capabilities found in Gmail.
Nonetheless, the core functionality the ability to chat with friends and family remained intact.
The service will go offline on June 26, 2024.
But… do you still remember your UIN?
We cover the most prominent areas of their history, innovations, successes and controversies.