Which image file format commonly used on the Web supports neither transparency nor animation?

The JPG file format, which stands for Joint Photographic Experts Group, is commonly used on the web primarily for photographs and images with rich colors. One of its critical characteristics is that it does not support transparency; any transparent areas would be filled with a default background color. Additionally, JPG does not support animation, meaning that multiple images cannot be contained in a single file to create a sequence or dynamic visual effects. This limitation makes JPG a suitable choice for static images but not for use cases requiring transparency or animation functionalities, unlike formats such as PNG or GIF, which do support one or the other, or both.