The ".icu" domain extension stands for "I See You." It was introduced as a generic top-level domain (gTLD) and is often used for a wide variety of websites. The ".icu" extension is popular for its short and catchy nature, making it memorable and versatile. It doesn’t have a specific industry association, so it can be used by businesses, personal blogs, social media profiles, or any type of website that wants a unique and easily recognizable domain name.