An image format defines how digital images are encoded and stored, influencing aspects like quality, compression, and compatibility.

Common formats include JPEG, PNG, GIF, and WebP, each with distinct characteristics. For instance, JPEG is widely used for photographs due to its balance between quality and file size, while PNG supports transparency and is ideal for graphics. Selecting the appropriate image format is essential for optimizing web performance and ensuring visual assets are displayed correctly across different devices and browsers.