Fluorescent ink is a special type of ink that glows brightly under ultraviolet (UV) light. This unique property makes it popular for various applications, such as in security printing for banknotes and art projects. When exposed to UV light, the ink absorbs energy and re-emits it as visible light, creating a vibrant effect. In addition to its use in security, fluorescent ink is also found in highlighters and neon signs. Artists often use it to create eye-catching designs that stand out in low-light conditions. Overall, fluorescent ink adds a fun and functional element to many creative and practical uses.