Which file extension is used for image files created by the Joint Photograph Experts Group?

The file extension used for image files created by the Joint Photographic Experts Group is .jpg. This format is specifically designed for compressing photographic images, making it ideal for storing and sharing digital photos. The compression techniques used in the .jpg format allow for smaller file sizes while maintaining a good balance of image quality, which is particularly beneficial for web use where faster loading times are important.

In contrast, the other file extensions serve different purposes: .png is used for images that require transparency and lossless compression, .gif is suited for simple animations and supports a limited color palette, and .pdf is primarily for documents rather than images. Understanding these distinctions helps in selecting the right file format based on the specific needs of an image or document.