APNG (Animated Portable Network Graphics) is a file format that extends the PNG (Portable Network Graphics) format to support animated images. It is similar to GIF, but offers better support for truecolor images and alpha transparency. APNG files are essentially sequences of PNG images that are displayed in rapid succession to create an animation. Each frame in an APNG file can have its own transparency and delay time, allowing for complex and visually appealing animations. APNG is particularly useful for creating animations with smooth transitions and detailed graphics, making it a popular choice for web animations, user interface elements, and other applications where high-quality animated images are required. While GIF remains widely supported, APNG provides a modern alternative with superior image quality and transparency capabilities. APNG is supported by most modern web browsers and image viewers.