ICQ is a cross-platform instant messaging and VoIP client. It is available for Windows, macOS, Linux, Android, iOS and web browsers. ICQ originally developed by the Israeli company Mirabilis in 1996. The name of ICQ contains the phrase "I Seek You".

ICQ allows users to send text messages, make voice and video calls, share files and locations, play games, use animated emoticons (smileys), and set up chatbots. Chatbots are third-party services that allow users to interact with ICQ without using the standard user interface.

ICQ also offers a number of features for enterprise users, including support for group chat, file sharing, and integration with popular business applications such as Salesforce, Zendesk, and Slack. ICQ is available in over 20 languages.